Tuesday, July 12, 2011
Discrete HTPC GPU Shootout
The popularity of Intel's HD Graphics amongst HTPC enthusiasts and the success of the AMD APUs seem to indicate that the days of the discrete HTPC GPU are numbered. However, for those with legacy systems, a discrete HTPC GPU will probably be the only way to enable hardware accelerated HD playback. In the meanwhile, discrete HTPC GPUs also aim to offer more video post processing capabilities.
In this context, both AMD and NVIDIA have been serving the market with their low end GPUs. These GPUs are preferable for HTPC scenarios due to their low power consumption and ability to be passively cooled. Today, we will be taking a look at four GPUs for which passively cooled solutions exist in the market. From AMD's side, we have the 6450 and 6570, while the GT 430 and GT 520 make up the numbers from the NVIDIA side.
Gaming benchmarks are not of much interest to the HTPC user interested in a passively cooled solution. Instead of focusing on that aspect, we will evaluate factors relevant to the AV experience. After taking a look at the paper specifications of the candidates, we will describe our evaluation testbed.
We will start off the hands-on evaluation with a presentation of the HQV benchmarks. This provides the first differentiating factor.
While almost all cards (including the integrated graphics on CPUs) are able to playback HD videos with some sort of acceleration, videophiles are more demanding. They want to customize the display refresh rate to match the source frame rate of the video being played. Casual HTPC users may not recognize the subtle issues created by mismatched refresh rates. However, improper deinterlacing may lead to highly noticeable issues. We will devote a couple of sections to see how the cards handle custom refresh rates and fare at deinterlacing.
After this, we will proceed to identify a benchmark for evaluating HTPC GPUs. This benchmark gives us an idea of how fast the GPUs can decode the supported codecs, and whether faster decoding implies more time for post processing. We will see one of the cards having insane decoding speeds, and try to find out why.
Over the last few months, we have also been keeping track of some exciting open source software in the HTPC area. Aiming to simplify the player setup and also take advantage of as many features of your GPU as possible, we believe these are very close to being ready for prime time. We will have a couple of sections covering the setup and usage of these tools.
Without further ado, let us go forward and take a look at the contenders.