AMD’s GTX 560 Ti Counter-Offensive: Radeon HD 6950 1GB & XFX’s Radeon HD 6870 Black Edition

After being AnandTech’s senior GPU editor for nearly a year and a half and through more late-night GPU launches than I care to count, there’s a very specific pattern I’ve picked up on: the GPU market may be competitive, but it’s the $200-$300 that really brings out the insanity. I’m not sure if it’s the volume, the profit margins, or just the desire to be seen as affordable, but AMD and NVIDIA seem to take out all the stops to one-up each other whenever either side plans on launching a new video card in this price range.
Today was originally supposed to be about the newly released GeForce GTX 560 Ti – NVIDIA’s new GF114-based $250 video card. Much as was the case with the launch of AMD’s Radeon HD 6800 series however, AMD is itching to spoil NVIDIA’s launch with their own push. Furthermore they intend to do so on two fronts: directly above the GTX 560 Ti at $259 is the Radeon HD 6950 1GB, and somewhere below it one of many factory overclocked Radeon HD 6870 cards, in our case an XFX Radeon HD 6870 Black Edition. The Radeon HD 6950 1GB is effectively the GTX 560 Ti’s direct competition, while the overclocked 6870 serves to be the price spoiler.
It wasn’t always meant to be this way, and indeed 5 days ago things were quite different. But before we get too far, let’s quickly discuss today’s cards.

	AMD Radeon HD 6970	AMD Radeon HD 6950 2GB	AMD Radeon HD 6950 1GB	XFX Radeon HD 6870 Black	AMD Radeon HD 6870
Stream Processors	1536	1408	1408	1120	1120
Texture Units	96	88	88	56	56
ROPs	32	32	32	32	32
Core Clock	880MHz	800MHz	800MHz	940MHz	900MHz
Memory Clock	1.375GHz (5.5GHz effective) GDDR5	1.25GHz (5.0GHz effective) GDDR5	1.25GHz (5.0GHz effective) GDDR5	1.15GHz (4.6GHz effective) GDDR5	1.05GHz (4.2GHz effective) GDDR5
Memory Bus Width	256-bit	256-bit	256-bit	256-bit	256-bit
Frame Buffer	2GB	2GB	1GB	1GB	1GB
FP64	1/4	1/4	1/4	N/A	N/A
Transistor Count	2.64B	2.64B	2.64B	1.7B	1.7B
Manufacturing Process	TSMC 40nm	TSMC 40nm	TSMC 40nm	TSMC 40nm	TSMC 40nm
Price Point	$369	~$279	$259	$229	~$219

Back when the Radeon HD 6950 launched, AMD told us to expect 1GB cards sometime in the near future as a value option. Because the 6900 series is using fairly new 2Gb GDDR5, such chips are still in short supply and cost more versus the very common and very available 1Gb variety. It’s not a massive difference once you all up the bill of materials on a video card, but for the card manufactures if they can save $10 on RAM then that’s $10 they can mark down a card and snag that many more sales. Furthermore we’re not quite to the point where 2GB is essential in the sub-$300 market - where 2560x1600 monitors are rare – so the performance penalty isn’t a major concern. As a result it was only a matter of time until 1GB 6900 series cards hit the market, to fill in the gap until 2Gb GDDR5 came down in price.

The day has finally come for the Radeon HD 6950 1GB, and today is that day. Truth be told it’s actually a bit anticlimactic – the reference 6950 1GB is virtually identical to the reference 6950 2GB. It’s the same PCB attached to the same vapor chamber cooler with the same power and heat characteristics. There is one and only one difference: the 1GB card uses 8 1Gb GDDR5 chips, and the 2GB card uses 8 2Gb GDDR5 chips. Everything else is equal, and indeed when the 6950 is not RAM limited even the performance is equal.
The second card we’re taking a quick look at is the XFX Radeon HD 6870 Black Edition, the obligatory factory overclocked Radeon HD 6870. Utilizing XFX’s open-air custom HSF, it’s clocked at 940MHz core and 1150MHz (4.6Gbps data rate) memory, representing a 40Mhz (4%) core overclock and a 100MHz (9%) memory overclock. Truth be told it’s not much of an overclock, and if it wasn’t for the cooler it wouldn’t be a very remarkable card as far as factory overclocking goes, and for that reason it’s almost a footnote today. But it wasn’t meant to be, and that’s where our story begins.