Thread: Video card crossfire question

Originally Posted by HeavyG

That is better, but is obviously a driver problem. This is similar to Crysis and Far Cry 2. Crossfire drivers just weren't working and would either crash, give no performance gain, or reduced performance gain. He was using 10.7 drivers to test that card when 10.8 and 10.9 drivers were out. Look at the comments and you can see they said the 10.10 drivers came out just after he published this review. In every single other test, the Crossfire scaling was terrific.

And to quote W1zzard from TechPowerUp:

"using directx 11 now. i rebenched all cards in wow for that. and crossfire does not properly support wow so the performance sucks"

AMD Radeon HD 6870 CrossFire - Page 3 - techPowerUp! Forums

So it is a problem with how he did his testing... Again, I wouldn't put my money on the results for this single test, especially since every other game had performance scaling increases around 90%.

Exactly. I was saying that Crossfire/SLI isn't supported for every game, and that not all games benefit from it. Granted a large portion of games to do benefit. From many benchmarks I've seen, SLI/CF hasn't really benefited in Blizzard games.

Benchmark Results: StarCraft II : AMD CrossFire Vs. Nvidia SLI Scaling Analysis

I think you are missing the point where it is the Crossfire drivers/profiles that are the issue... not the game. Typically, if the drivers don't work or the profiles for the game are borked, then you will likely see poor performance.

Read the note at the bottom where it says "StarCraft 2 is clearly bottlenecked by our host platform. But CrossFire is performing very poorly here in comparison to the competition, with the single-card performance faring better than two cards in CrossFire mode. Hopefully, AMD will address this problem with a Catalyst Control Center profile update in the near future."

Notice that the 2560x1600 SLI configurations the GTX 460s have a 41% performance increase, the GTX 470s have a 19% performance increase, and the GTX 480s have only a 5% performance increase. This supports the fact that dual GPUs are providing quite a large performance increase with the mid range cards. The GTX 480s are having a slight performance increase, but not as much as a single card can probably process close to the maximum frame rates.

Again, I am not purposely trying to argue, but the evidence is clear that unless there is a software/driver issue, having 2 GPUs will almost always provide a benefit, no matter how big or small. These blizzard games obviously have some bugs when it comes to ATI drivers and profiles, but the nVIDIA cards are giving some nice performance increases... especially those GTX 460s!

My point being... don't rely on the graphs. The ATI/AMD cards obviously have some issues. Back when I had my dual ATI 4850s in Crossfire, I would always have problems after driver updates, especially with Bad Company 2. I remember one update that cut my FPS in half because the driver profiles were not ready and the game was not optimized for the new drivers. I had to fall back to older drivers and profiles to get it running good again.

ATI was really struggling for a while, but it seems this year has been better for them on the driver side of things.

Originally Posted by HeavyG

My point being... don't rely on the graphs. The ATI/AMD cards obviously have some issues. Back when I had my dual ATI 4850s in Crossfire, I would always have problems after driver updates, especially with Bad Company 2. I remember one update that cut my FPS in half because the driver profiles were not ready and the game was not optimized for the new drivers. I had to fall back to older drivers and profiles to get it running good again.

ATI was really struggling for a while, but it seems this year has been better for them on the driver side of things.

Well I was just merely just wanted to point out that not all games gained FPS or had a positive result from Crossfire/SLI. I'm not trying to argue the reason whether it be driver or just the game or what not, just saying that there isn't always a positive gain from the dual cards.

I just don't want people to get the impression that SLI/Crossfire is a BAD idea. If they have the money and want better frame rates, higher resolution, and higher detail settings, then SLI/Crossfire is a GOOD idea. It is much cheaper to buy a 2nd card of what you already have then to buy a high end single card while likely achieving equal or better performance than the single high end card.

Going around posting a few flawed tests with bad drivers or poorly designed benchmarks (W1zzard's DX11 WOW test) can give people the wrong impression. While it may be important to see these bad tests, I think it is much more important seeing the benefits of SLI/Crossfire, which are many.