Tuesday, November 30, 2010

Do Virus Scanners Slow Down Your System?

Does the presence of a virus scanner guarantee reduced performance, or does it have a negligible impact? We test 10 different products to see if you’re unknowingly suffering with security software.
Remember the days of Windows 98, when CPUs ran at triple-digit MHz speeds and slogged along with less than a gigabyte of RAM? Installing a resident program like a virus scanner often meant committing performance suicide. And heaven forbid a scheduled scan start up while you were actually at your desk. Productivity could literally grind to a halt. At least that’s how I remember things through the fog of time.
Today's personal computers are much more powerful than they were a few years ago, so perhaps the notion that an anti-virus application will still have a debilitating effect on performance is obsolete. Still, folks who began using computers after multi-core CPUs and gigabytes of RAM became the norm have likely never used a PC without a virus scanner installed. They'd have no way to relate to the days of running lean and mean to keep speed manageable. Now we have resources to spare. Cores sit idle, waiting for a task to execute, while low prices on memory make 6 GB and 8 GB kits affordable for even mainstream users.
We should make this perfectly clear: while it’s undeniable that an active virus scan can cause a heavy performance burden, what we’re really curious about is whether or not performance is affected when a system scan is not running. Does it take longer to open files when you have a resident virus scanner installed? Does the presence of the software tax CPU resources while you’re running other programs? What kind of tasks are most affected by security products, if any?
When faced with these sorts of questions, it’s only natural that we’d run some tests to unearth the real answers—this is Tom’s Hardware, after all. So let’s look a little deeper into quantifying the anti-virus conundrum.
What Does A Virus Scanner Do?
Before we begin our tests, we should at least consider how virus scanners work so that we can see if the results are in sync with our expectations.

There are two main mechanisms that most virus scanners use in order to keep your system safe: file checking and behavior monitoring.

File checking is by far the most prevalent technique. The idea is simple: the virus scanner examines the files on your PC for known threats, a threat being a signature of code that is associated with a particular virus. Because new viruses are being released all the time, most virus scanners will periodically download updates containing the new threat signatures.

How could file checking affect performance? Typically, a virus scanner will examine files for threat signatures every time a file is written, opened, closed, or emailed, or when a virus scan occurs. It thus makes sense to predict that applications accessing files on a regular basis might be slowed down by anti-virus software. Conversely, programs that don't involve a lot of file access might then remain relatively unaffected by the presence of a virus scanner.

Behavior monitoring is the second technology that anti-virus software employs to identify threats. This is a pre-emptive strategy to deal with viruses that have not yet been identified or added to the threat-signature dictionary. The virus scanner monitors the system for suspicious behavior, such as the alteration of executable files. This virus-prevention technique probably has very little effect on system performance, since suspicious behavior is probably somewhat rare.

That should be enough of a top-down overview to get us started. Let's get on with the tests!

We begin by selecting the security software to test. We're curious to find out if Internet security suites might contain bloatware that could slow down a system more than a simple anti-virus program would, so we've included not only virus scanners, but also complete Internet security suites offered by noteworthy developers. This means we’re testing AVG Anti-Virus 9.0, AVG Internet Security 9.0, Kaspersky Anti-Virus 2011, Kaspersky Internet Security 2011, McAfee VirusScan Plus, McAfee Internet Security, Norton AntiVirus 2010, Norton Internet Security 2010, Trend Micro Titanium AntiVirus+, and Trend Micro Titanium Internet Security.
Where benchmarks are concerned, we’ve assembled a suite of tests to exercise most aspects of PC performance, from gaming to office work. We’re testing raw application performance and also the time it takes for the system to respond to boot and to program launch requests. In order to do this, we’ve even developed some custom benchmarks, courtesy of our own Andrew Ku.
While we're running the benchmarks on an Athlon II X4 645, we'll be disabling two of the CPU cores for the majority of benchmarks. As a result, most of the benchmarks reflect the performance users can expect from a budget dual-core CPU. On page seven we run more benchmarks with only a single CPU core enabled, and also with all four CPU cores enabled, to see if the performance burden changes based on the number of execution cores available to the system.
With all this in mind, here are the particulars for our test system and benchmarks:
  Test System
MotherboardAsus M4A785TD-V EVO Socket AM3, AMD 785G, BIOS 0410
ProcessorAthlon II X4 645
3.1 GHz, Quad-Core CPU
Multiplier set to 3.0 GHz
Single- and quad-cores enabled for CPU core comparison on page 7
CPU CoolerCooler Master Hyper TX3
MemoryCrucial DDR3-1333
Dual-Channel 2 x 2048 MB, 669 MHz,
CAS 9-9-9-24-1T
GraphicsRadeon HD 5830 Reference
1 GB GDDR5, 800 MHz GPU, 1000 MHz Memory
Hard DriveWestern Digital Caviar Black 1000 MB
7200 RPM, 32 MB Cache SATA 3Gb/s
Software and Drivers
Operating SystemMicrosoft Windows 7 x64
DirectX VersionDirectX 11
Graphics DriversAMD Catalyst 10.9

And here's a list of the benchmarks:
Benchmark Configuration
3D Games
CrysisPatch 1.2.1, DirectX 10, 64-bit executable, benchmark tool
High Quality, No AA
Audio/Video Encoding
TMPGEnc 4.0 ExpressVersion:
Import File: "Terminator 2" SE DVD (5 Minutes)
Resolution: 720x576 (PAL) 16:9
Xvid 1.2.2Display encoding status = off
WinRAR 3.90Version x64 3.90, Dictionary = 4096 KB, Benchmark: THG-Workload (334 MB)
Synthetic Benchmarks
PCMark VantageVersion: x64, All Benchmarks
SiSoftware Sandra 2010Version 2010.1.16.11, CPU Test = CPU Arithmetic

We should preface the following CPU and game benchmarks by saying we really don't expect security software to have an effect on them. Anti-virus software typically activates on the creation, opening, closing, or emailing of files, and none of the following tasks are focused on any of these activities. Regardless, we make no assumptions and perform the following tests to check our theory.

We start things off with a synthetic CPU benchmark to see whether or not these products will cause performance differences compared to a computer without any security software installed. As you can see, the presence of this software appears to cause no tangible impact on raw processing performance.
Now let’s see what happens in a real-world encoding application.

Encoding a video with the Xvid codec definitely stresses the processor—in fact, it stresses the whole platform. Nevertheless, there’s no real performance difference to see here.

We benchmarked Crysis to see if any of these security software products would affect game performance. Happily, it does not appear to have any impact whatsoever.

The following benchmarks involve hard drive and file access, which a virus scanner could theoretically affect.

The results are close across the board with our first file access benchmark, the PCMark hard drive test score. It has been our experience that PCMark results have a larger margin of error than what we’d prefer, so we won’t draw any specific conclusions from this close result.

Moving to a real-world benchmark that involves compressing 334 MB of files, our WinRAR test doesn’t expose any obvious weaknesses in file system performance.

It can be difficult to define and measure the general responsiveness of a PC, yet the productivity and communications benchmarks that are part of the PCMark Vantage suite are probably well-suited for this test.

The PCMark Vantage communications benchmark includes a combination of tests that cover common tasks like data encryption, compression, Web page rendering, and Windows Mail searches. Past experience with PCMark shows that the margin of error can be a little larger than what we’d like it to be and the score with no security software running is actually lower than some results when virus scanners and Internet security suites are running. We consequently can’t draw any conclusions from these results, but can see that there isn’t a large difference when any of these products are used.

The productivity benchmark suite includes common tasks like starting applications, editing documents in WordPad, and searching contacts using Windows Search. There is a multitasking portion of this benchmark that runs three simultaneous tasks, including a Windows Contact search and Windows Mail message rules and renders numerous Web pages in Internet Explorer. Finally, this bench includes a number of hard disk stressing tasks, such as a Windows Defender scan and a boot timer.
As you can see, there are definitely some strong trends here that suggest this benchmark is affected by security software to varying degrees, but Kaspersky and Trend Micro products appear to suffer a large performance penalty.
Let’s dig deeper into the PCMark productivity benchmark specifically to see exactly what tasks are running slower when antivirus software installed:

Very interesting. First, let’s look at the productivity tasks that are not affected by the presence of these scanners. All of the hard disk-intensive tasks, such as Windows Vista startup, Windows Defender, and application loading, perform no differently with or without security software installed. This result supports our previous hard drive test results that also demonstrate little or no performance penalties due to a resident virus scanner. Aside from this, text editing a Word document also shows no performance differential.
On the other hand, a Windows Contacts search operation demonstrates a sizable performance penalty when Kaspersky or Trend Micro security software is installed. Note that the Productivity 4 Windows Contacts search occurs during multitasking, but both results are similar. The other operation that appears to be affected by the presence of security software is Web page rendering, also recorded during multi-tasking operations.
On a final note, we should mention that we left one of the PCMark productivity benchmarks out of the above chart. The Productivity 4 Windows Mail copying benchmark provides very inconsistent results in our testing, reporting anywhere between one and six operations per second.

It is our intention to benchmark the boot time with these different security solutions installed, and we spent a lot of time testing this using GreenVantage’s WinBootInfo utility. Unfortunately, the results we recorded show a huge variance from 30 to 60 seconds, even when taken one after the other, and we’re not comfortable releasing these results even after averaging multiple iterations. What we will say is that all of the averages we recorded are between 32 and 46 seconds. With boot times ranging from 30 to 60 seconds, there probably isn’t any significant conclusion to draw.
The response time benchmarks we demonstrate below are much more consistent. We open a document in Word and a LAN-hosted Web page in Firefox. Here’s how long it takes, on average, to open these files the first time after a fresh boot into Windows:

While we do experience significant variance between minimum and maximum load times for each security software package, with six iterations averaged, we see some clear trends across Firefox and Word. Most notably, AVG, McAfee, and Trend Micro products seem to take a little longer to open files than their competitors. McAfee Internet Security, specifically, has a longer wait time to launch the test Web page.
Speaking of McAfee, with this product installed, we notice a colossal lag to launch the timer application we developed to record benchmark results. When I say colossal, I mean it takes the better part of 10 seconds to launch the tiny program—an application that executes instantly with any other anti-virus program we tested. The reason for this appears to be that McAfee’s real-time scanning method is based on checking against known application signatures. Since McAfee obviously can’t have signatures for custom-made applications, it will thoroughly scan the application in question before launch. It does seem to take longer than it should to accomplish this task. We’re asking McAfee about this and hope to have an answer before publication—otherwise, we will follow up in a future article.
Back to the results, though. The bar graphs do make it appear that there is a large variance on first load, but we’re talking about a two to five-and-a-half second spread to open Firefox and a three-to-six-second spread to open a Word document. It sounds worse than it feels, as those extra few seconds don’t seem all that obvious. Admittedly, that’s a subjective argument.
What is objective is that the same application loads much faster the second time it is launched during a Windows session:

The difference in application launch speeds is reduced to less than a second between competing security software solutions on subsequent runs of the same program. This is a short enough time span that it's difficult to notice any change at all during real-world use.

We think it’s important to address one of the variables missing from our previous tests, and that is hardware. As we’ve seen up until this point, most applications don’t seem to show a notable difference in performance, regardless of whether security software is installed or not. But all of the tests have also been run on a dual-core CPU, too. Will the results change on a single- or quad-core processor?
We would expect the raw performance to drop slightly in multithreaded applications. But we're curious about the effect security software has on single-core performance, too. While we don’t have time to run the entire benchmark suite for different processor setups, we run all three CPU options with AVG AntiVirus 9, AVG Internet Security 9, and without any security software installed for a quick test:

While the number of available execution cores can certainly affect the raw results, when it comes to comparing performance on the basis of available compute resources, the only metric that shows a significant performance drop associated with a single-core processor running security software is the time it takes to load Internet pages on the first run. Aside from that, security software doesn’t seem to have an adverse affect on single-core PCs. This is a surprising result, as we expected security software to take advantage of threading. It’s possible that our test scenarios don’t give the software an ideal opportunity to do so, but it’s a surprising result nonetheless.

As mentioned on the first page, I came into this story idea aware that I had a prejudiced expectation. Although I’d never actually tested it for myself, I was under the impression that the presence of a resident virus scanner would have an adverse effect on system performance.
I’m very happy to report that my preconceptions have no place in today’s PC world, as even single-core processors are able to demonstrate comparable performance with or without modern security software installed. This is true not only for basic virus scanners, but also for comprehensive security suites.
Having said that, it’s also true that the presence of security software isn’t undetectable in all circumstances. We do see an increase in application launch times with a virus scanner installed, but the only significant wait time is a couple seconds added on the first launch of a program. Subsequent launches appear to be cached, and the wait time is almost imperceptible.
The only benchmark that shows a notable performance decrease with a virus scanner installed is PCMark’s productivity suite. Even here the performance hit is only notable with two of the 10 tested security products, and in this case, an increase in Windows Contacts search times is the main cause. While I can’t speak for everyone I know, I do not spend a significant amount of time searching Windows Contacts, so for me this isn’t much of an issue.
While these results are encouraging, a couple of questions need to be answered. As we mentioned at the beginning, we’ve limited our testing to performance with the virus scanner installed. However, what is the performance hit during an actual virus scan? This is something we hope to examine in a follow-up review in the near future.
However, for the time being, we’ve learned that a user can confidently install a virus scanner or Internet security suite without being too concerned about performance consequences. It appears that typical tasks we undertake when using our PCs will not be notably slowed by the security software on which we rely. In the end, I’m pleased to admit that my expectation of a decrease in general PC performance when a virus scanner is installed was incorrect and obsolete.


A brief look at upcoming ASUS P67 Motherboards

On first inspection, this board’s aesthetic blue and black livery is impressive.   The big blue heatsinks on the VRM, while looking good with a large surface area, intrude slightly on the socket, potentially resulting in restricting the orientation of high end air coolers.
Among the standard features you’d expect on a P67, such as the four dual-channel DDR3 slots, and four SATA 3Gb/s with two SATA 6Gb/s supported by the chipset, there is another two SATA ports, but it is unclear if these are for the RAID, 3Gb/s or 6Gb/s, or how they are powered, as they are not labelled and the chipset heatsink covers quite a bit.  Two NEC controllers give two USB 3.0 ports on the back panel, and the possibility for another two via a header on the board connectable to the case, or to an ASUS USB 3.0 port box (as shown in the P67 Deluxe images).  The Sandy Bridge platform on P67 relies on discrete graphics only, and as such there are no video out connectors on the back panel, but two PCIe x8 slots on the board itself (or one PCIe x16 if only one card is used).  There is another PCIe slot available, presumably x4, for non-GPU duties.
The back panel itself is fairly standard – dual PS/2 ports for keyboard and mouse, S/PDIF out, six USB 2.0 ports, two USB 3.0 ports, two eSATA connectors, firewire, 5.1 audio and gigabit Ethernet.  Also of note is the Bluetooth receiver, which is a nice addition, but the lack of a second gigabit Ethernet port, which by now we feel should be a staple on all high end boards and any board with the ‘Pro’ moniker, isn’t too pleasing. 
On the board, we see two switches for TPU (TurboV Processing Unit) and EPU (Energy Processing Unit).  The TPU is designed to monitor FET thermal temperatures, while the EPU will moderate power appropriately across the VRMs. Both can be turned on and off by the onboard switches, and presumably in the BIOS as well.
Speaking of switches, we’re disappointed that ASUS have not put easy-to-use power and reset switches on the Pro.  Sure, not everyone needs them, but they are a nice addition rather than having to short two front panel pins with a screwdriver (when slightly tired, it’s never a good idea to accidentally short the wrong pins, unless you want to see some sparks).

Comcast 'Toll Booth' for Netflix Revives Net Neutrality

An additional fee to stream Netflix movies to Comcast customers has created a real-life example for advocates of Net neutrality. Comcast imposed the fee on Level 3 Communications, part of the Netflix broadband backbone. Level 3 called the fee a "toll booth" on competition and appealed to regulators, including the FCC.

The fight for Net neutrality now has a practical case that could affect the future of streaming media on the web. Comcast is requiring that a major Internet service provider pay an additional fee for delivering Netflix's streaming movies.
The fee is being imposed on Level 3 Communications, one of the broadband backbone networks that Netflix uses to provide its newly expanded streaming service. The movie service, which made its name by providing DVD rentals in red envelopes via the U.S. Post Office, has steadily been increasing the films available for immediate streaming over broadband connections. Recently, it launched a streaming-only membership option.
'Threatens the Open Internet'
On Monday, Level 3 issued a statement that it had been informed on Nov. 19 by Comcast that there will be a "recurring fee from Level 3 to transmit Internet online Relevant Products/Services movies and other content Relevant Products/Services to Comcast's customers who request such content."
Level 3 called the fee a "toll booth" allowing Comcast to "unilaterally decide how much to charge for content which competes with its own cable-TV and Xfinity delivered content."
Level 3 added that the action "threatens the open Internet and is a clear abuse of the dominant control" Comcast has as the nation's largest cable provider. The backbone provider said it accepted the payment terms "under protest" to ensure customers would not experience disruptions.
Level 3 said it is asking regulators and policy-makers for action to ensure that "a fair, open and innovative Internet does not become a closed network Relevant Products/Services controlled by a few institutions."
Comcast said its payment demand was being "misportrayed" by Level 3, and was only part of the "commercial negotiations" between the companies. It said the fee "has nothing to do with Level 3's desire to distribute different types of network traffic," but instead reflects the cable company's "established" commercial arrangements with content delivery networks.
'Information' vs 'Telecommunications' Service
In addition to offering a wide variety of premium cable movie channels and on-demand films that conflict with Netflix, Comcast is also expected to launch TV Everywhere next month. That service will allow Comcast subscribers to watch movies and TV shows over the web from a variety of devices.
Comcast has been at the center of the Net-neutrality storm. A Federal Communications Commission ruling against Comcast for imposing bandwidth restrictions on a file-sharing application Relevant Products/Services -- without first informing customers -- was seen as the opening battle in the Net-neutrality fight, since the app could be used to distribute movies. In April, a federal court found that the FCC overstepped its authority under its current classification of Net providers as "information Relevant Products/Services services."
Since then, FCC Chairman Julius Genachowski has proposed a modified reclassification of broadband service as a "telecommunications service." That would allow the agency to require that Comcast and others transmit all content and non-malicious applications equally -- the core feature of Net neutrality.

Edward Scissorhands 300MB Dvdrip MKV

Edward Scissorhands 410MB Dvdrip MKV

Subtitle : English
Format : Matroska
File size : 410 MiB
Duration : 1h 41mn
Overall bit rate : 549 Kbps
Width : 640 pixels
Height : 352 pixels
Frame rate : 23.976 fps
Audio Format : AAC
BitRate : 128KB


Howls Moving Castle 300MB Dvdrip MKV

Howls Moving Castle 305MB Dvdrip MKV

Subtitle             : English
File size                        : 320 MiB
Duration                         : 1h 55mn
Overall bit rate                 : 362 Kbps
Width                            : 640 pixels
Height                           : 352 pixels
Frame rate                       : 23.976 fps
Audio Format                           : AAC
Bitrate                : 128kb


Monday, November 29, 2010

Roundup: Four Radeon HD 6850 1 GB Cards Compared

Improvements to performance, acoustics, and bundles can add big value once a reference graphics card is modified by third-party vendors. We compare four modified Radeon HD 6850 1 GB boards to find out which company's additions best suit your gaming needs.
Some say green is the new red, and no place is that more true than in the rebranding of ATI to AMD. And yet, marketing similarities between AMD and Nvidia don’t end in color, as the newer, more efficient Radeon HD 6850 offers performance and a price nearly identical to Nvidia's GeForce GTX 460 1 GB. If you want to know more about the card itself, check out our launch review of the Radeon HD 6870 and 6850.
AMD’s slightly better power consumption figures mean that buyers of the new green team can go green for the same green, while saving a little green over the life of the card (Ed.: Xzibit approves, dawg).

If you believe this makes the Radeon HD 6850 a perfect mid-priced performance part, you're in good company, as the number of folks willing to spend ~$200 is much greater than the market for flagship $500 boards.
If you're ready to buy, there are plenty of options available. Some vendors even offer multiple models. Choosing a card certainly doesn’t have to be difficult. We simply asked every major manufacturer to send its best, and those who didn’t have anything to offer beyond AMD's reference design chose not to participate. That left us with four souped-up models for your consideration.

Radeon HD 6850 1 GB Comparison Specifications
Asus EAH6850
MSI R6850
PowerColor AX6850
Sapphire Toxic 6850
GPU Clock790 MHz775 MHz820 MHz820 MHz
DRAM RateGDDR5-4000GDDR5-4000GDDR5-4400GDDR5-4400
DVITwo Dual-LinkTwo Dual-LinkTwo Dual-LinkTwo Dual-Link
DisplayPortFull-SizeFull-SizeFull-SizeDual Mini
VGABy Adapter (x1)By Adapter (x1)By Adapter (x1)By Adapter (x1)
Mini to Full DP
Weight18 Ounces16 Ounces19 Ounces27 Ounces
PCB VersionC223 Rev. 1.00V224 V1.0LF R97FF V1.0109-C22237-00
VRMThree PhasesThree PhasesFour PhasesFour Phases
WarrantyThree YearsThree YearsTwo YearsTwo Years
Added ValuePCIe Power Adapter
CrossFire Bridge
CD Wallet
PCIe Power Adapter
CrossFire Bridge
CrossFire Bridge
Free "Call of Duty:
Modern Warfare 2"
6' HDMI Cable
2 x PCIe Power Adapter
CrossFire Bridge
Price$200 $205 $210 $210 

Also known as model EAH6850 DC/2DIS/1GD5, Asus’ barely-overclocked Radeon HD 6850 includes enhanced cooling and advanced voltage control to let buyers decide the best performance-to-noise ratio.

A custom 9.7” circuit board faces its single six-pin PCIe power connector, easing installation into shorter cases. The DirectCU heat pipes add around 3/8” to the cooler’s height without affecting power connector placement, while a steel rail on the card’s top edge braces it against the extra weight of that cooler.

Placement into narrow cases or certain space-saving cube designs could potentially be problematic, but Asus’ design makes sense for the majority of performance PC builders.

Clocked only 15 MHz higher than AMD’s reference GPU specification and with no bump in memory frequency, the EAH6850 DC/2DIS/1GD5 offers builders a core voltage range of 0.95 to 1.35 V to do their own custom tuning.

Asus SmartDoctor provides the EAH6850 DC/2DIS/1GD5 slide controls for voltage, GPU, and DRAM frequencies from its main menu. Users can select GPU frequencies between 600 and 1000 MHz, DRAM data rates between 3000 and 5000 MT/s, and core voltage from 0.95 to 1.35 V.

Advanced menus control overheat protection, alarm settings, and startup options.

A third advanced menu allows fan speed to be set at four thermal presets. Lower temperatures can help overclockers achieve higher settings.

SmartDoctor’s HyperDrive menu allows users to set an active GPU clock boost, activated when a 3D game is detected.

A quick look at the package reveals that our test unit is the OC Edition of MSI’s R6850 PM2D1GD5, separated from MSI’s reference-speed R6850 PM2D1GD5 only by clock rate.

The difficulties we had trying to set this article up at the end of October are bluntly revealed in this board. The OC Edition was initially listed on MSI’s Web site, only to disappear later. AMD’s Radeon HD 6850 graphics processor has little room to overclock at or near stock core voltage, and MSI cancelled its OC Edition card rather than risk instability.

Several factors caused us to keep MSI in the running for this roundup. First is that all our reference-clocked cards are dispersed across other test labs around the country, and including one as a reference point in this story is a useful way to show how much better overclocked samples perform.
Second is that the OC Edition card uses the same hardware as MSI’s standard-edition R6850 PM2D1GD5, so that underclocking allows the faster card to represent the performance level of its reference-clocked sibling.

The R6850 PM2D1GD5 uses the same 8.5”-long circuit board design as the HIS model from our launch article, with three of its four voltage regulators enabled. While the cooler extends the card’s overall length, the 8.6” distance from the card’s face to the end of its PCIe power connector will be more important to those who plan to use a small case.

The current version of MSI Afterburner did not support voltage changes on this particular card as of this writing, though MSI has fixed this missing option in past cards through Afterburner updates. Other functions already work perfectly, including core clock, memory clock, fan speed, and advanced controls.

While manual changes stick between reboots, advanced fan maps require the software to be running. We believe MSI’s fan mapping is the best in the industry, and startup options allow it to launch automatically and be minimized to the task bar.

Monitoring, logging, and OSD options take up two more pages of the advanced menu.

MSI adds a screen capture function that automatically saves a game image.

Up to four overclocked configurations can be saved as profiles, with launch options that include game-based performance increases.

One of the two highest-clocked samples in today’s roundup, PowerColor’s PCS+ AX6850 sweetens the deal with a free download of Call of Duty: Modern Warfare 2.

That “deal” is for a card that includes a four-phase voltage regulator to stably support its high clock rates on a circuit board that’s only 8.5” long. Identical in other ways to MSI’s PCB, the 8.6” distance between the slot plate and the end of its PCIe power connector allows reasonable cable clearance in tight cases. A plastic cover over the card's cooling fan extends its total mounting depth to 8.9".

Clock rates of 820 MHz GPU and GDDR5-4400 are sure to boost the PCS+ AX6850’s frame rates to performance levels not consistently supported by MSI’s similar three-phase design. A slightly larger heat sink keeps things cool under the added load.

PowerColor does not yet offer an overclocking utility for its Radeon HD 6850 cards, but users can always try one from a third party.

Registration gets PCS+ AX6850 buyers a month of VIP access to SuperStar Racing, an online multiplayer formula racing game.

Sapphire does things its own way, beginning with an oversized blow-through cooler on its part number 100315TXSR Toxic 6850.

Sapphire buyers get a surprising array of upgrades, from the card’s dual mini-DisplayPort outputs (and single full-sized adapter) to its inclusion of a six-foot HDMI cable. Sapphire even throws in two four-pin Molex to six-pin PCIe power adapter cables.

The dual power adapters make sense in light of the fact that Sapphire puts two six-pin PCIe power connectors on its card. Sapphire’s entire design is borrowed from the Radeon HD 6870, stretching the card to a 9.6” mounted length, while adding the handy feature of a card that vents out the back of the case.

Even though Sapphire’s Toxic 6850 is oversized, it uses the same 820 MHz GPU and GDDR5-4400 clocks as the smaller PowerColor competitor in today’s comparison. Rather than include software, Sapphire adds onboard features and cables to make its Toxic 6850 unique.

Sapphire doesn’t have an overclocking utility for its 6850 cards, though third-party utilities often support this model

Test System Configuration
CPUIntel Core i7-980X (3.33 GHz, 12 MB Shared L3 Cache)
Overclocked to 4 GHz at +100 mV, 160 MHz BCLK
MotherboardGigabyte X58A-UD9 BIOS F3 (05/28/2010)
Intel X58 Express, LGA 1366
RAMKingston KHX16000D3ULT1K3/6GX (6 GB)
DDR3-2000 at DDR3-1600 CAS 7-7-7-21
OS Hard DriveWestern Digital Velociraptor WD3000HLFS, 300 GB
10 000 RPM, SATA 3Gb/s, 16 MB cache
SoundIntegrated HD Audio
NetworkIntegrated Gigabit Networking
PowerOCZ-Z1000M 1000 W Modular, ATX12V v2.2, EPS12V, 80 PLUS Gold
OSMicrosoft Windows 7 Ultimate 64-bit
GeForce GraphicsForceWare 258.96
Radeon GraphicsAMD Catalyst 10.10
ChipsetIntel INF

Gigabyte’s four-way CrossFire/SLI-supporting motherboard provides today’s test cards with all the performance they need, while opening up the possibility of future CrossFire scaling articles using some of today’s data.
Clock speed has often been our biggest bottleneck in achieving full graphics card performance. None of our games require more than three processing cores, yet Intel’s six-core Core i7-980X is already in the board and easily supports 4 GHz overclocked.

OCZ’s Z1000M provides over 88% efficiency across a very broad range of loads, at minimal noise.

Benchmark Configuration
3D Games
Aliens Vs. Predator BenchmarkAlien vs Predator Benchmark Tool
Test Set 1: Highest Settings, No AA
Test Set 2: Highest Settings, 4x AA
Call of Duty: Modern Warfare 2Campaign, Act III, Second Sun (45 sec. FRAPS)
Test Set 1: Highest Settings, No AA
Test Set 2: Highest Settings, 4x AA
CrysisPatch 1.2.1, DirectX 10, 64-bit executable, benchmark tool
Test Set 1: Highest Quality, No AA
Test Set 2: Highest Quality, 4x AA
DiRT 2Run with -benchmark example_benchmark.xml
Test Set 1: Highest Settings, No AA
Test Set 2: Highest Settings, 4x AA
S.T.A.L.K.E.R.: Call Of PripyatCall Of Pripyat Benchmark version
Test Set 1: Highest Settings, No AA
Test Set 2: Highest Settings, 4x MSAA
Synthetic Benchmarks and Settings
3DMark VantageVersion: 1.0.1, GPU and CPU scores
Power, Heat, and Noise
GPU LoadFurMark 1.6.5 Stability Test, 1920x1200, 4x AA
P3 Kill A Watt P4400Global Power Consumption at AC outlet
Galaxy Check Mate CM-140Measured at 1/4 meter, corrected to 1 m (-12 db)

This author’s argument against definitive noise measurements is that it’s almost impossible to remove background noise contamination from a running system. Yet, many readers insist that these measurements must be taken for relativity's sake. Using a “supersized” CPU air cooler that takes several minutes to warm up, the CPU fan has been temporarily disconnected during sound tests to get a somewhat-close approximation of each card’s true noise level.

The Call of Pripyat benchmark has, in the past, been an exceedingly strenuous workload for mid-range graphics cards. And yet, all four Radeon HD 6850s breeze through our 1680x1050 test.

Slow frame rates at our target 1920x1080 resolution with 4x AA enabled force us again to look at test notes. Sapphire and PowerColor each had a minimum 20 FPS, while Asus and MSI dropped to 19 and 18 FPS, respectively.

All four cards appear playable at 2560x1600, yet another look at our test notes showed a failing 14-15 FPS minimum for every card, with AA disabled. You're simply going to want something faster to play this game at these settings.

3DMark scores don’t mean much in the real world, but we did notice the scores in today’s Radeon HD 6850 roundup are very similar to those generated in our previous GeForce GTX 460 reviews. That similarity is partly due to disabling the PPU test, which we feel gives Nvidia an artificial and unrealistic advantage.

Voltage and clock speed have adverse effects on power consumption, so we expect the fastest cards to fall to the bottom of our power chart.

Asus has surprisingly low power consumption compared to MSI, and even the slightest power advantage for Sapphire’s oversized card surprises us when compared to PowerColor. We wonder why Sapphire needed to include two PCIe connectors?

Sapphire edges out PowerColor in average frame rate, but margins this small could be pure variance.
This is where our match gets tedious. We wanted to base our efficiency number purely on averages, so we first averaged the No AA and 4x AA average frame rates of each card. We then calculated a class average by averaging our list of averages. For those following along, the class average is 49.8 FPS.
Dividing each card’s average by the class average puts its performance level on a percent scale, where “zero difference” is actually 100% and the top cards are higher. Following the same procedure for Full Load and Idle power gives us a similar percent scale where the most miserly cards have the lowest score. Dividing those results gives use a calculation of efficiency, where class average is 100%.

Yet no electronic component is 100% efficient. We subtracted 1 from each card’s result to move the chart scale by 100%, focusing only on the differences in efficiency. Asus’ lower-power “mid-speed” card is 3.9% more efficient than the class average, while Sapphire’s moderate power consumption makes it the most efficient “fast” card.

Heat and noise output are controlled not just by the GPU voltage and clock, but by the cooler design. Asus surprised us by having the lowest temperature, since the card was also relatively quiet. Sapphire takes second place when its fan is turned to max speed.

Quiet coolers are often sub-par when dealing with heat, but Asus proved the contrary with its DirectCU design. The chart below is not perfectly accurate, since some background noise was unavoidable.

Sapphire has the noisiest card. But looking beyond the card itself, there is an advantage to its noisier, blower-type fan. That advantage is case cooling, since the Sapphire Toxic 6850 is the only card in today’s comparison to vent most of its heat outside of the case. We’ve previously seen the consequences of using internally-vented cards in an extreme CPU configuration.

Following a similar method to that of our previous-page’s energy efficiency calculations, we compared temperature to noise for today’s cards. Note that the temperature division is “flipped over” in this case to give the lowest temperature the highest score, and that the “acoustic efficiency” chart does not account for performance differences.

Sapphire and PowerColor have the best-performing graphics cards, but who has the best performance-value? We averaged the price of all four cards, then divided the actual price by the class average to put each card on a percent scale.

Based solely on a comparison of price to performance, Asus wins. Yet, unlike PowerColor, Asus does not include a free game certificate with its card. If you don't already own Call of Duty and that bundled item is important to you, then the balance shifts toward PowerColor's offering. Likewise, Sapphire is the only company to include a free HDMI cable with its card. So if the card is going into a home theater environment and you're missing HDMI connectivity, Sapphire's inclusion is more meaningful. Both Sapphire and PowerColor provide marginally better performance than Asus, and the packaged bonus features for both Sapphire and PowerColor come at a mere $10 price premium compared to Asus.
So, which card would we chose? This tester would probably pick the Asus EAH6850 DirectCU Overclock Edition for its low noise. But then again this tester already has HDMI cables and more game licenses than he can ever use.
If this was a System Builder Marathon, I’d probably go with two Sapphire Toxic 6850 cards for their externally-vented design. Pushing graphics heat out of the case would allow a more aggressive CPU overclock, and the CPU is a big bottleneck in multiple-GPU configurations.
If I were building for someone else, I would probably choose the PowerColor PCS+ AX6850 for its high speed, moderately-low noise, and free game. That special someone would probably value the extra software worth anywhere from thirty to fifty dollars online. Now, where did I put that Christmas list?