Value & Conclusion

When I first heard about the opportunity to play with QuadSLI vs. Crossfire I expected QuadSLI to have a significant advantage over Crossfire but at an equally significant price difference.

Now I am very disappointed. The driver installation seems to be very unstable. Also it seems nobody tested these cards on an ASUS board, where you have to change a BIOS setting to get the cards stable. The performance is absolutely not what you would expect from a "technology leader", "best of CES" product. In some benchmarks two ATI video cards were a great deal faster, even at the high resolutions which NVIDIA says are the key benefits of QuadSLI.

Even more humiliating was that one single 7900 GX2 often runs faster than two GX2 in QuadSLI.

Dear NVIDIA,
I have a great performance improvement suggestion for your next QuadSLI driver release:
if ((resolutionX<1600) && (resolutionY<1200))
   DisableQuadSLI();

If you already have a Ferrari and a nice boat and now need something new to impress your friends you could shell out at least 7k for a Quad SLI system and a 30" widescreen gaming display. All other users may want to go for a more cost-effective and stable solution.

Over the years NVIDIA has greatly improved their SLI drivers to be rock stable and very performance efficient. If they can do the same to their Quad-SLI drivers I think we will see a winner. But until then you better wait till the quirks are sorted out.

Quad-SLI seems to be a very promising solution. Hats off to the engineers who managed to stuff so much GPU power into so little space without any thermal or power issues. Now it's time that the driver gurus make full use of this power.

Our other tested system was ATI's X1900 XTX Crossfire. Even though ATI entered the multi-GPU market a lot later than NVIDIA, they successfully improved their product and now have a very competitive solution. When asked about Quad-Crossfire ATI told us that they "are looking into it". Right now ATI has the better solution for gaming at maximum detail at ultra-high wide-screen resolutions.

UPDATE: (May 03)
I just had a phonecall with NVIDIA. They want to emphasize that QuadSLI is built for ultra-high-res gaming at at least SLI 8xAA. If you don't have a wide-screen high-res display, regular SLI will be a more cost effective solution for you, they say.
Also QuadSLI is designed to give you the very best image quality and visual experience at the highest possible settings with playable framerates, not unnecessary high framerates at low quality. Your flatscreen will not be able to display more than 60 to 70 frames/second anyway.



About the hardware/driver issues I had, they mentioned that the current 7900 GX2 QuadSLI is meant to be sold exclusively by system integrators. Which means you get a turnkey system which is already preinstalled at the best settings and does not require any further installation or configuration. If you want to build your own, you should wait until the GeForce 7950 GX2 cards are released which will be some time in June. These have an improved PCB which is not so long and also require only one power connector.