Conclusions
For most intents, Nvidia's G92 is currently the finest graphics processor on the planet. That fact shined through as we tested the GeForce 9800 GTX as a single graphics card, and it consistently performed—as expected—better than almost any single-GPU card available. I say "almost" because the older GeForce 8800 Ultra outran it at times, but I say "available" tentatively, because the Ultra is beginning to look scarce these days. The Ultra has its drawbacks, too. It doesn't support all of the latest features for HD movie playback, such as HDCP over dual-link DVI or H.264 decode acceleration. It draws a lot of power. And at its best, the 8800 Ultra cost about twice what the 9800 GTX now does. If you're looking for a high-end graphics card and don't want to go the multi-GPU route, the GeForce 9800 GTX is the way to go.

The G92 GPU's sheer potency creates a problem for Nvidia, though, when it becomes the building block for three- and four-way multi-GPU solutions. We saw iffy scaling with these configs in much of our testing, but I don't really blame Nvidia or its technology. The truth is that today's games, displays, and CPUs aren't yet ready to take advantage of the GPU power they're offering in these ultra-exclusive high-end configurations. For the most part, we tested with quality settings about as good as they get. (I suppose we could have tested with 16X CSAA enabled or the like, but we know from experience that brings a fairly modest increase in visual fidelity along with a modest performance penalty.) In nearly every case, dual G92s proved to be more than adequate at 2560x1600. We didn't have this same problem when we tested CrossFire X. AMD's work on performance optimizations deserves to be lauded, but one of the reasons CrossFire X scales relatively well is that the RV670 GPU is a slower building block. Two G92 GPUs consistently perform as well as three or four RV670s, and they therefore run into a whole different set of scaling problems as the GPU count rises.

Crysis performance remains something of an exception and an enigma. We now know several things about it. As we learned here, the game doesn't really seem to benefit from going from two CPU cores to four. We know that two G92s in SLI can run the game pretty well at 1920x1200 using its "high" quality settings. "Very high" is a bit of a stretch, and three- and four-way SLI don't appear to be any help. We also know this game will bump up against memory size limits with 512MB of video memory, especially with GeForce cards and current drivers. Crysis would seem to be the one opportunity for the G92 SLI configs to really show what they can do, but instead, it's the older GeForce 8800 Ultra with 768MB of memory that ends up stealing the show. The Ultra also proves to be faster in CoD4 and Quake Wars at 2560x1600, thanks to its larger memory size and higher memory bandwidth.

So G92-based three- and four-way SLI remains a solution waiting for a problem—one that doesn't involve memory size or bandwidth limitations, it would seem.

Personally, I'm quite happy to see the pendulum swing this way, for GPU power to outdistance what game developers are throwing at it. Now, a $199 card like the GeForce 9600 GT can deliver a very nice experience for most folks. If you want more power, the 9800 GTX is a solid option that doesn't involve the compatibility issues that SLI and CrossFire bring with them. Yet I also can't wait to see what these sort of high-end solutions could do when put to full and proper use. Unfortunately, we may have to wait until the current wave of console ports and cross-developed games passes before we find out.