The Definitive Multi-GPU World Tour - Conclusion #3

The Crossfire & SLI effect

What is the sole purpose of getting a multi-GPU setup ? Obviously even better performance compared to single GPU gameplay is the answer to that question. If you pair that 7600 GS/X1600 Pro you will get a better framerate plain and simple. If you choose high-end multi-GPU gaming you'll receive some extra cream on top of that already delicious ice cream as you get to play your games in even higher resolutions with better "super" AA modes. 9 out of 10 users will also stick at 16x anisotropic filtering with 4 levels of Anti aliasing enabled, there's just no denying that.

Now, you are on Guru3D.com and we won't leave you hanging dry with some sort of results of our own. We can look at this article overview from many points of view. One of the things I figured would be interesting to do is have a look at all resolutions and simply crunch the data published by the other sites. How many wins did ATI get per resolution and how many did NVIDIA get. Interesting for sure, yet I admit very subjective. Because if card A is rendering 99 frames per second and the other 97 would that really make a difference ? No, of course not.

So bare with me here and look at it as merely an indication. I highly recommend you to look at the article, then look up your favorite games and resolutions and then compare to see what is the best solution for you.

We selected the graphics cards based on a roughly equal price configuration:

• Two Radeon X1600 Pro's equal two GeForce 7600 GS videocards.
• Two Radeon X1900 GT's equal one GeForce 7950 GX2 videocard.
• Two X1900 XTs equal two GeForce 7900 GTX videocards.

Again, match the price. We figured that each setup should also require a proper mainboard. In total we simply defined the setups at sub $1,000 US, sub $2,000 US, and unlimited budget. Please have a look at Pentarsys for what everyone did in terms of selection of the components.

1. $1,000 US - AMD Athlon X2 3800+, 1 GB (2 x 512 MB) of PC3200 DDR, 2x GeForce 7600 GS @ nForce 4 SLI and  2x Radeon X1600 Pro @ Xpress 1600
2. $2,000 US - AMD Athlon X2 4400+, 2 GB (2 x 1024 MB) of PC3200 DDR, 1x GeForce 7950 GX2 GS @ nForce 4 SLI 32x  and Radeon 2x X1900GT @ Xpress 3200
3. Unlimited budget - AMD Athlon FX-62 (AM2), 2 GB (2 x 1024 MB) of PC6400 DDR2, 2x GeForce 7900 GTX @ nForce 590 SLI and Radeon 2x X1900 XT @ Xpress 3200

We can go extremely in-depth into the performance per setup here but there's no point as overall it's clear NVIDIA has a lead of a year and that shows. NVIDIA are winning pretty much the majority of benchmarks that are produced by these sites. Crossfire just does not scale as well as SLI does. Whether that is mainboard or videocard related it all boils to the same conclusion NVIDIA dominates the scores as presented to you by the other participating websites.

And although I should not defend it as my job is to analyze and present the outcome that the other sites have cooked up for you my bet is that you should definitely not rule out ATI here as they are far from done with Crossfire development. In the extreme high-resolutions with complex AA settings you'll notice that ATI is doing a pretty impressive job. Have a look at Legit Reviews for example who were able to use that new Catalyst 6.7 driver.

Now initially Guru3D wanted to tally up all results from all articles. Yet there was a lot of resistance from the participating websites and only two websites submitted their tally to us. The most representable and up-to-date of these tally results I believed could be found at Legit Reviews & Rage3D as they used the 6.7 Catalyst driver.

As submitted by Legit reviews:

• Low End: Nvidia Wins 30 - 3
• Mid-Range: Nvidia Wins 27-4
• High-End: ATI Wins 9-8

As submitted by Rage3D:

• Low End: Nvidia Wins 42 - 0
• Mid-Range: Nvidia Wins 42-32
• High-End: pending

If we tally up the results from them we see NVIDIA obviously dominate everything, even in certain games if ATI is winning NVIDIA remains really close, especially in low and mid-range performance systems ATI is under attack. But very interesting to see is how the high-end products from ATI perform with that new Cat 6.7 driver. Be sure to check that out.

In short: the overall view among the majority of games without a doubt is looking fantastic for NVIDIA SLI. Nobody will deny that even for a second. But do remember what I already stated in the introduction, the last two or three sites have used the new Catalyst 6.7 drivers in their scores (they received them prior to the official release form ATI) and they clearly make a distinct performance difference. None the less. NVIDIA takes the lead by far.

But there is much more to all this than a tally of results. Let's talk a little about Image Quality, HDR+AA and drivers.

Drivers

Any piece of hardware is only as good as it's driver allows it to be. Both ATI and NVIDIA provide really good driver support with ATI taking on the lead with steady regular monthly driver releases. This hint is something NVIDIA should really pick up for a change as driver support is lacking due to the slow updates. From the Multi-GPU point of view both drivers work great. It's just so easy to setup either SLI or Crossfire.

NVIDIA however had the pilot two and a half years ago in it's ForceWare driver development with SLI, and that unmistakably shows. Multi-GPU configurations are easy to enable on both platforms yet NVIDIA offers very extensive game performance profiles which will allow you to setup the game with various IQ en multi-gpu rendering (AFR/SFR) methods. This is the enthusiast game and users absolutely prefer this and it's a far better solution then ATI has with it's Catalyst drivers at the moment. There's is nothing complex about NVIDIA's ForceWare drivers which is just fantastic, except the new style control panel that is, and I'll get into that in a moment.

ATI then, what's good about the new Catalyst drivers is that pretty much all low/mid and even the X1900 GT (supported soon) can run Crossfire without the need for a more expensive mastercard and no need for that dreaded Crossfire y-cable. That offers great flexibility. You do not need to bridge the cards with a connector of some sort as all data is being transferred over the PCI-Express lanes, quite lovely. But all cards utilizing this new feature were showing less performance compared to the master/slave card configuration.

Something else I find really interesting is that the new Catalyst drivers drivers will also allow you to use non-crossfire mainboards like Intel's 975 platform and others to be handle Crossfire. This means you are not 100% platform dependant and that is a big win for ATI although I'm not certain how that'll develop in the future though as AMD is buying ATI. So on the long term Intel will likely revoke that license. The same can be said for NVIDIA. Guru3D has no clue what the long term relationship with ATI deeply merged into AMD will mean for AMD's versus NVIDIA's business. Then again AMD is not stupid and NVIDIA means business for them.

Anyway back to the actual article. NVIDIA SLI products will require the SLI bridge and they will force you to run SLI on an SLI capable mainboard. They are making sure you spend your coins on their products.

So in short, NVIDIA has a good development advantage on it's SLI drivers and that shows. The majority of benchmarks show really good support for a broad amount of games. ATI's catalyst drivers have matured and slowly we're seeing better Crossfire support. You can expect monthly updates which is just fantastic. NVIDIA can and should learn from that. Why do you think there are so many beta drivers floating around ? Exactly my point.

On another note, a more practical one, I do find the Catalyst CCC drivers slow to load up and navigate through, that's next to eating away 300 to 400 MB on your HD. Catalyst drivers are a resource hog and that's still something I still can't get used to.

Funnily enough for whatever vague reason NVIDIA recently stepped away from their "classic" design Control Panel also and are slowly introducing the ForceWare drivers based on a new design Control Panel. I'd like to address a few things here to NVIDIA.

My dear NVIDIA. Your drivers are really fantastic but the new CP looks like we are back in 1995 when I first installed Windows 95. It truely is not an easy to navigate and comprehend GUI. It is rather user unfriendly and looks like something a third grade programmer built with Visual basic. Guru3D absolutely does not like the new layout at all and the majority of consumers find it to be a labyrinth. Can someone please tell me the advantage of the new CP over the classic design ? The old design was clear, easy to use and straight forward.

And just in case you think I'm the only one:

NVIDIA's ForceWare control panel. What do you like better ?

I like the old Classic design  73%   I like the new design  14%   Neither, NVIDIA should revamp the CP completely  13%

Therefore NVIDIA please have a look at this Poll we recently took, please take the hint. Listen to your audience. We need regular driver updates and an actual control panel one can navigate and understand easily. As you can see this is a very critical point for me personally at the moment.

NVIDIA's GeForce 7900 GTX 512 MB in SLI. I call this "The Brick" setup ;)