ATI Radeon X700 vs The Midrange

The Radeon X700 XT is a very similar size to the GeForce 6600GT and it's interesting to see the different cooling methods that are used on the two boards. The heatsink design on the X700 series has already been discussed on the previous page. The GeForce 6600GT currently has quieter operation - the fan is a larger 50mm design, while the heatsink is constructed in aluminium. There were slight thermal issues with the X700 XT, but we would put this down to the fact that the board is a first generation sample. We've been informed that the specific board that we tested did have thermal issues and, as always, we will confirm this when we get the chance to test another X700 XT at a later date.


* - the GeForce 6600GT can only output four pixels per clock. The internal pipeline structure allows for eight pixels to be operated on per clock cycle, but due to the cut down pixel output engine structure, it is only able to write four pixels at a time. The GeForce 6600GT does appear to have eight pixel shader/texture units, which means that it’s not a strict 8x1 design, or a 4x1 design. It’s a hybrid design that is aided by a feature that NVIDIA refer to as a "Fragment Crossbar". The fragment crossbar essentially assigns the pixels final processing stages to any available pixel output engine (also known as a ROP unit). This basically aids the GPU’s efficiency by removing the possibilities of pipeline stalls and allowing the pixel shading units to work with a high efficiency. This is quite a smart design, and real world performance is certainly not affected by the hybrid structure to the NV43 GPU.

The X700 XT lines up almost identically to the GeForce 6600GT, the clocks are slightly different, but where the GeForce 6600GT has a higher core clock, the X700 XT makes up for this with a higher Memory clock. The performance of these two boards should, most definitely, be quite a closely fought contest. The GeForceFX is equipped with very high memory bandwidth and a high core clock, but the strict 4x2 pipeline configuration really limits the real-world performance. It will be interesting to see how well the GeForceFX 59x0 series and Radeon 9800 series line up against the two new mainstream boards.



A final shot of the Radeon X700 XT along side the GeForce 6600GT...