I replaced a fried motherboard and got an ASUS P4 V 800. The ASUS Probe shows the temp on the CPU at a cool 28-32 and motherboard is 30-32. My chasis fan seems to change RPM and is somewhere around 1200 rpm but the CPU fan is stuck at an annoyingly loud 5700 rpm. This is the third motherboard (I got two defective motherboards) from :unch: ASUS and I'd rather not get stuck with another RMA, everything else seems to be fine with this mobo. Do you think its the board or the fan? The fan came with the CPU, a P4 2.6GHz. But I changed the case and the chasis fan recently too, the new power supply is a 350 W Antec.