The Tests - An Overclocking Orgy
280 MHz FSB ran stably - to get more juice out of it, we would have had to use considerably more effort.
Our overclocking tests made it quickly clear that the 925XE is a twin sibling of the 925X. With both of the Asus boards (P5AD2 and P5GD2) and an ATI Radeon X600, we were able to attain a 280 MHz FSB clock with very little fine tuning - theoretically, that corresponds to FSB1120. Thanks to the new DDR2 667 memory module, a memory clock of up to 374 MHz (DDR2 748) is also possible at the same time. With DDR2 553 memory, the clock ratio had to be changed from 3:4 to 1:1, so that the memory clock wouldn't become too high.
The test system revealed no real faults - we only had to reboot once during the benchmarks at 280 MHz FSB. At FSB1066 or 266 MHz, we still could not find any weak points, even with a continuous load through Prime95 and the burn-in test from Sandra 2004. This makes it clear that the chipset has already got what it takes.
In our previous experiences with Serial-ATA hard drives, we weren't able to get the overclocking results that we wanted. For this reason, we used the WD800JB, an UltraATA/100 hard drive from Western Digital, for the test. It turned out to be a good choice, because we weren't able to get such high clock rates with SATA components on any of the boards - 250-265 MHz was the limit.
We also did not have much success with NVIDIA's GeForce 6800 GT, which does not take much more than about 260 MHz FSB and a correspondingly high PCI Express clock. Unfortunately, overclocking the system doesn't work very well when the PCI Express clock is limited to 100 MHz.