Version 2.5.3 runs smoothly on my server (Windows 2003, Apache 2) but it shows a wrong bus speed and cache size in the hardware box. They should be 133 MHz and 512 kB respectively.
Check it here: http://agentsmith.mine.nu/phpsysinfo/
Version 2.5.4 has the same problem and so does 3.0_RC2 unfortunately. Any chance this will be fixed in a future version?
Can you run this php script and copy the result here please ?