i just built me up another pc. AMD athlonxp 1800, Abit NF7 mb. for some reason reboots periodically, i've checked and double checked everything, and i mean everything. the only thing that might have been a problem is, in the bios, the cpu fsb/dram ratio was set to "By SPD" instead of "Auto". i have three pcs and ive checked all hardware between them and eveythings fine. its not heat or voltage, ive been monitoring that and its all fine. ive check in event viewer and all is says is that its been restarted from a bug check. no system errors or program errors. any ideas?