Compared to AMD’s gracefully engineered Radeon 3870 X2, Nvidia’s GeForce 9800 GX2 (represented here by Gigabyte’s implementation) is something of a kludge. But when we consider the performance that Nvidia’s design delivers, it’s hard to complain about elegance.
Both AMD’s and Nvidia’s solutions deliver dual-GPU performance from a single PCI Express slot without requiring chipset support (and in both cases, adding chipset support allows you to run four GPUs in one system). AMD’s solution, however, plants two Radeon 3870 GPUs and two 512MB frame buffers on a single printed circuit board; Nvidia’s design entails taking two PCBs (each with a G92 processor and 512MB of GDDR3 memory), bolting them together, and sticking a ribbon cable in between. It’s a quick-and-dirty brute-force solution, but it delivers frame rates like nobody’s business.
Gigabyte hewed closely to Nvidia’s reference design, clocking the GPU cores at 600MHz, the shaders at 1.5GHz, and the memory at 1GHz. Pay no attention to what Nvidia’s website says, the chip’s memory interface is 256 bits wide, not 512. It seems both Nvidia and AMD have realized that wider interfaces weren’t delivering as much performance as they had anticipated; these days, 256-bit memory interfaces are de rigueur even at the high end.
We’ve given up benchmarking Crysis at 1920x1200, and no card has yet delivered what we’d call acceptable performance even with the 1280x720, 2x AA settings we’ve been using—until now: The 9800 GX2 pumped out 41.4 frames per second. Maximum PC readers don’t live by games alone, and you obviously don’t need two G92s to watch a Blu-ray movie, but we’re happy to report that the 9800 GX2 includes Nvidia’s excellent PureVideoHD for offloading high-definition video decoding from the host CPU. The HDMI socket on the mounting bracket saves you from having to use an adapter, but getting digital audio to that connector involves another kludge: a cable from your motherboard header to a socket on the card (AMD’s solution routes digital audio over the bus).
But if we can’t have both, we’ll take beast over beauty any day of the week.
Great for gaming. HDMI on the mounting bracket.
Kinda kludgy—especially the audio cable for the HDMI port.
Gigabyte GeForce 9800 X2
MSI Radeon 3870 X2
3DMark06 Game 1 (FPS)
3DMark06 Game 2 (FPS)
Crysis (DX9) (FPS)
Unreal Tournament 3 (FPS)
Best scores are bolded. AMD-based cards tested with an Intel D975BX2 motherboard; Nvidia-based cards tested with an EVGA 680i SLI motherboard. Intel 2.93GHz Core 2 Extreme X6800 CPUs and 2GB of Corsair DDR RAM used in both scenarios. Benchmarks performed on ViewSonic VP2330wb monitors. For Vista results, see http://tinyurl.com/3ss7s2.