ATI's RD580: ASUS A8R32-MVP Deluxe

Gaming Performance - 2:

First off, we can't directly compare the dual card performance of ATI's RD580 chipset with NVIDIA's nForce4 SLI x16, because the GPUs are in a different class. However, we can get some idea of how efficient each architecture is when it comes to the difference between two PCI-Express x8 slots and two PCI-Express x16 slots.

We saw a single frame per second increase between CrossFire on RD580 and RD480 chipsets, while NVIDIA's SLI showed an increase of two frames per second. However, it's worth noting that this could be down to the fact that Radeon X1900 CrossFire is quite a bit faster than GeForce 7800 GT SLI, meaning that the performance delta might be slightly CPU limited.

The ASUS A8R-MVP was the slowest board in single card mode, while the other three boards all performed the same, returning a 35 frame per second average frame rate.

The ASUS A8N32-SLI was slower than the other boards by around 2 frames per second in single card mode, while the A8R32-MVP was the fastest and closely followed by the two dual PCI-Express x8 boards.

There was a four and a half frame per second performance incresae between RD480 and RD580 when using two Radeon X1900's in CrossFire mode. Meanwhile, the difference between nForce4 SLI and nForce4 SLI X16 was a mere one frame per second. We understand that the larger performance increases come from using the likes of SuperAA and SLI AA - we'll update our numbers with some additional game testing with these antialiasing modes later this week.

Again, there were small performance increases with conventional antialiasing modes as a result of the increased bandwidth across the two video card interconnects, but we feel that larger performance increases will be seen when we use the dual card specific AA modes.

The ASUS A8N32-SLI Deluxe was slightly faster than the CrossFire Xpress 3200-based A8R32-MVP when using a single GeForce 7800 GT OC. However, we're talking about less than a 0.5 frames per second difference between the two boards. Interestingly, the dual x8 cards were both slower than their dual x16 siblings.