Dear All, I have installed Centos 4.3 64bit on an Athlon 64 3700 running in a Sapphire Radeon Xpress chipset based motherboard. It has SATA2 disks, and the chipset works fine under Linux, gives good i/o performance etc. However, the Linux clock runs about 2.5x normal rate, [ so this machine is well into next week already!] Yet when you reboot it and look at the bios time it says the correct time and the clock runs at the right speed. When the system boot back into Linux, the clock starts off at the right time again but then goes racing forwards at more than double speed . It seems the kernel can't count the ticks correctly. Even the watch command can't count seconds correctly so "watch date" updates every second, which of course the system thinks is two seconds I tried both the 2.6.9-34 and 2.6.9-34-01 kernels with the same result. I might change the mobo, Does anyone else have any ideas? P.