Introduction

Last week we took a look at the performance of ATI’s latest graphics card, the Radeon X1950 XTX and found the card to be a more than capable performer, in fact it delivered the best performance of any GPU we’ve tested. Despite this however, the title of fastest graphics card still belonged to the dual-GPU GeForce 7950 GX2. Even with its 1GHz (2GHz effective) GDDR4 memory modules, the Radeon X1950 XTX just couldn’t keep up with the GeForce 7950 GX2 (with the exception to that being Oblivion). In our conclusion we guessed that part of the reason why the X1950 XTX performs so similarly to the Radeon X1900 XTX it replaces is because ATI’s GDDR4 modules are operating at higher latency and/or memory timings than the GDDR3 modules used on the older X1900 XTX. We summed the article up on a positive note though saying: “ATI’s Radeon X1950 XTX builds largely on foundation laid with the Radeon X1900 XTX. ATI’s basically resolved the XTX board’s biggest issue – noise – with the Radeon X1950 XTX, and spiced the package up by including HDCP support as well as outfitting the board with faster GDDR4 memory. This change nets the X1950 XTX slightly more performance, which is never a bad thing.”

Today we’re taking a look at the Radeon X1950 XTX CrossFire Edition card, the companion card of the Radeon X1950 XTX we previewed last week. The X1950 XTX CrossFire shares the same clock speeds as the X1950 XTX, 650MHz core/1.0GHz memory (2.0GHz effective), and supports all the Radeon X1950 XTX’s new features, most notably HDCP support (via DVI) and the X1950 XTX’s new heat pipe cooling.

In comparison to previous CrossFire boards, ATI’s made no changes to the Radeon X1950 XTX CrossFire, the board relies on the same compositing engine first introduced with the Radeon X1800 XT CrossFire Edition and also uses the same dongle system ATI has used on previous CrossFire boards. In the case of the compositing engine, this is certainly a good thing, as the Xilinx FPGA at the heart of ATI’s compositing engine handles the blending used for CrossFire’s Super AA mode. With blending handled in hardware, enabling ATI’s Super AA modes with newer CrossFire cards comes at a significantly reduced performance hit.

In the past we’ve shown you how ATI’s Radeon X1900 CrossFire and X1800 XT CrossFire stack up against NVIDIA’s GeForce cards when the two are running their respective 8x, 14x, and 16xAA modes, finding that ATI’s cards deliver significantly greater performance.


But how do a pair of Radeon X1950 XTX CrossFire cards perform in comparison to NVIDIA’s mighty GeForce 7950 GX2 Quad SLI? That’s precisely what we set out to test in today’s article.