nVidia GeForce 9800 GX2 (G92) Review Edition

@ Anandtech
With G9x coming in as a glorified die shrink to G80, NVIDIA took the opportunity to move away from huge die size and shift to the cheaper option of combining two GPUs on a single board for its highest end part. It is less expensive to make use of two chips, even if their combined size is larger than a monolithic one because yields are so much better. NVIDIA is able to get more chips per wafer and a higher percentage of those will be good compared to a large design. Of course, in spite of a cheaper to produce solution, the increased performance of this solution over previous high end has earned the 9800 GX2 a pretty heft price premium. At a retail price of at least $600 US, these bad boys will not be making their way into everyone's systems. There is always a price for having the best of the best.

@ PC Perspective
We can remember first "officially" seeing the GeForce 9800 GX2 back in January when another website featured a few high resolution images of it. It definitely didn't LOOK like any other graphics card on the market at the time, with its fully enclosed cooling design and oddly stacked DVI outputs. We got another "clue" when NVIDIA itself mentioned the 9800 GX2 in a press FAQ about the launch of AMD's Radeon HD 3870 X2 card. Just like the HD 3870 X2, the new NVIDIA GeForce 9800 GX2 is a dual-GPU graphics board with only a single connection to the motherboard via PCI Express. The common way of describing these cards is "SLI on a card" or "CrossFire on a card" depending on your party affiliation. These descriptions are about as accurate as you can get in ten words or less, though as we'll see the NVIDIA 9800 GX2 is even more like "SLI on a card" than its AMD competition.

@ Hot Hardware
As you can see, the GPU is built using a 65nm fabrication process. On stock GeForce 9800 GX2 cards, the GPUs are clocked at 600MHz, with a 1.5GHz shader clock, and 1GHz memory. If you recall, the GeForce 8800 GTS 512MB's GPU is clocked at 670MHz with 900MHz memory, so a pair of GTS cards running in SLI mode will offer higher shader performance and fillrate, but less memory bandwidth. Keep that in mind as you look through the benchmark results that appear a little later in this article. The GeForce 9800 GX2 offers a total of 128GB/s of memory bandwidth, with a 1GB frame buffer (512MB per GPU), 32 ROPs (16 per GPU), and 128 Texture Filtering Units (64 per GPU), for a total of 76.8GigaTexels/sec.

XFX 9800 GX2 @ Legit Reviews
The GeForce 9800 GX2 is the latest flagship graphics card by NVIDIA and comes with a pair of GeForce G92 GPU's and 1GB of GDDR3 memory on board. With a total of about 1.5 billion transistors it will give the ATI Radeon HD 3870 X2 a run for its money. The new GeForce 9800 GX2 features 256 processor cores each independently operating at 1,500 MHz. Counting conservatively (2 flops per processor core), this amounts to an unprecedented 768 gigaflops of raw shading horsepower. In texturing performance, it can filter 76.8 billion pixels per second, or 190% more than the Radeon 3870 X2. In raw specifications across the board, it is vastly improved over its predecessor, the GeForce 8800 Ultra. But with a price of $599-$649, it launches at the same price that the GeForce 8800 GTX did back in 2006. With more than twice the shading power and a vastly improved PureVideo HD engine, the GeForce 9800 GX2 is something that all enthusiasts need to take a closer look at.

@ HardOCP
Each GPU has 128 shader processors, same as the GeForce 8800 GTS 512MB. Remember, the GeForce 8800 GT has 112 stream processors. But here is where things get odd. Both GPUs in the GeForce 9800 GX2 are clocked at a 600 MHz core frequency. This is actually lower than the GeForce 8800 GTS 512MB which is clocked at 650 MHz. Looking further we also see that the stream processors are clocked at 1.5 GHz. Well, this again is lower than the GeForce 8800 GTS 512MB which has its stream processors clocked at 1.625 GHz. So right off the bat, each GPU in the GeForce 9800 GX2 is clocked at the same frequency as a GeForce 8800 GT, BUT, they have 128 stream processors each, just like the 8800 GTS 512MB. So what we end up with is basically lower clocked GeForce 8800 GTS 512MB GPUs on board.

One can surmise that a single-board GeForce 9800 GX2's performance scaling will be good. After all, it's not that difficult to scale with two GPUs - both NVIDIA and AMD (ATI) have compelling multi-GPU technologies that leverage two GPUs in an efficient manner. The real pain the posterior will reside with scaling with to four GPUs, based on two 9800 GX2s boards in SLI. Queuing up the requisite number of frames is hugely problematic in Windows XP and highly dependent on the games' engines in Vista. NVIDIA will introduce four-way alternate frame rendering (AFR) with the 9800 GX2 SLI driver. The GeForce 9800 GX2 carries NVIDIA's PureVideo HD that has been software-upgraded with the release of the ForceWare 174.xx drivers. NVIDIA has added dynamic contrast and colour enhancements for better-looking images, it says. Further, the driver supports dual-stream decode, which hardware-accelerates the decoding of two video streams running concurrently. There are only few instances where we can see this being useful - picture-in-picture commentary, for example.