The last card in to our Labs was Nvidia’s new 9800 GX2. As the name suggests, it’s a dual-GPU card in the same mould as AMD’s HD 3870 X2, though unlike the AMD card it uses two physical printed circuit boards (PCBs), rather than two chips mounted on a single board.
It’s huge, requiring six-pin and eight-pin power connectors, and Nvidia recommends at least a 580W power supply. Thermal design power (TDP) is high too at 197W, so the usual large fans are present – though it’s not too noisy.
Although it’s the latest of Nvidia’s “next generation” cards, it’s based on the 65nm G92 core already seen in the 8800 GTS and the 9800 GTX (above). However, to reduce heat, the internal speeds are down-clocked: the core frequency is 600MHz and the shader clock runs at 1.5GHz (like the 8800 GT). The memory clock, however, matches the 8800 GTS’s 2GHz.
Where the GX2 comes into its own is parallel processing power: its 256 stream processors, divided between two GPUs, represent the highest shader count of any Nvidia card to date. It also supports quad-SLI although, as with the HD 3870 X2, this really means you’re still limited to two physical cards. We couldn’t get a second card before going to press.
Standard models come with a total of 1GB of graphics RAM (512MB per PCB), but we expect some Nvidia partners to increase this to a full gigabyte on each PCB, providing an unprecedentedly huge frame buffer.
Performance in some games will be heavily influenced by games’ SLI profiles but we were impressed in our benchmarks. In our 1600 x 1200 tests it managed 44fps in Crysis (10fps more than the 9800 GTX) and 82fps in Call of Duty (12fps more than the 9800 GTX and 8fps more than the 3870 X2). It was also the only card that could smoothly (for the most part) play Crysis at Very High settings scoring 28fps in this test (the 3870 X2 scored 21fps and the 9800 GTX scored 17fps).
At $700 it’s expensive, but it allows those without Nvidia motherboards to use SLI power. It’s also the only card that can play the best new games at 1600 x 1200 in all their glory and, arguably more importantly for the company, regains Nvidia the top performance crown.
This Review appeared in the June, 2008 issue of PC & Tech Authority Magazine
Source: Copyright © PC Pro, Dennis Publishing