Nvidia's Geforce GTX 285 is based on the same NVIDIA GT200 GPU architecture that's inside the Geforce GTX 280, but with a few noticeable tweaks, overclocks and a die shrink that has caused NVIDIA to rename it the GT200b.

Given the size of the naked nVidia GT200b GPU, it's not so surprising that to hear it contains 240 stream processors and 1.4 Billion transistors. Thanks to a 55nm die-shrink NVIDIA is able to pack these transistors into a smaller package. While the die of the original NVIDIA GT200 was 576mm2, the GT200b has been brought down to approximately 425mm2. Still, nVidia is in desperate need of a 40nm, or 32nm die shrink.

Default clock speed of the Geforce GTX 285 is 648MHz, on the Gigabyte GV-N285OC-2GI it has been factory overclocked to 660MHz. GPU communicates over a 512-bit wide memory interface, and it basically offers the highest core, shader and memory clock speeds of any desktop NVIDIA graphics card.

NVIDIA's GT200b graphics processing unit is very much a match for ATI's R700 GPU. While the ATI videocards have more on-board stream processors and faster memory, the NVIDIA videocards compensate by having faster faster shader clocks and wider memory interfaces. The end result is a pair of GPUs that have very different architectures, but still manage to achieve very similar performance.

NVIDIA GT200 vs ATI R700 Videocards
Models	Core clock	Stream processors/Clock	Memory Clock/Interface	Memory capacity	Market
Radeon HD 4870X2	750MHz	1600/750MHz	3600MHz/256-bit	2048MB	Flagship
Radeon HD 4890	850MHz	800/850MHz	3900MHz/256-bit	1024MB	High-end
Radeon HD 4870	750MHz	800/750MHz	3600MHz/256-bit	1024MB	Mainstream
Radeon HD 4850	625MHz	800/625MHz	1986MHz/256-bit	512MB	Mainstream
Geforce GTX 295	576MHz	480/1242MHz	2000MHz/448-bit	1792MB	Flagship
Gigabyte GV-N285OC-2GI	660MHz	240/1498Mhz	2400Mhz/512-bit	2048MHz	Flagship
Geforce GTX 285	648MHz	240/1476MHz	2484MHz/512-bit	1024MB	High-end
Geforce GTX 280	602MHz	240/1296MHz	2214MHz/512-bit	1024MB	High-end
Geforce GTX 275	633MHz	240/1404MHz	2268MHz/448-bit	896MB	Mainstream
Geforce GTX 260	576MHz	216/1350MHz	2000MHz/448-bit	896MB	Mainstream

Of course, the Gigabyte GV-N285OC-2GI videocard that PCSTATS is looking at today has been substantially modified from the original Geforce GTX 285 reference design. Gigabyte has doubled the amount of available memory to a whopping 2048MB of GDDR3. There are a few benefits to having such a huge amount of on-board memory, most of which come when running games at very high resolutions (think 2560 x 1600) or span multiple monitors. The extra memory is also useful when it comes to turning on eye candy like 16xAA. While most users won't have any conventional use for this much video memory, this is far from a conventional videocard, and will likely be used in very exotic system configurations.