Hi everyone, After leaving my pc on for an extended amount of time I notice my monitor flashing black. You can hear the monitor click, and then the image comes back a second later. These are some observations I made: -When the flashing occurs, my cpu load shoots from idle to about 70-80% -Activity seems to stop just before the flash, I know this because my cursor doesn’t highlight items just before the flash and the cursor becomes a little sluggish. -When I quickly play though my songlist in winamp (repeatedly press next) this encourages flashing. -The flashing is unpredictable I can have the machine run for a week fine then it happens all of a sudden. I reboot its still there. I reboot a little later an it’s gone... -The temps inside my case are all normal and I don't believe anything is overheating. -I also run ubuntu on the same machine and none of these problems are apparent. -This started happening after I cleaned out my pc and upgraded the RAM with 512x2 of OCZ. I tried without and the flashing hasn't happened yet. Although, this rarely ever happens anyway. Is there a way of checking what’s causing the problem? ---- cpu: 3.4 p4 prescott mobo: Intel 915pbl RAM: 256x2 OCZ DDRII(533mhz) 512x2 OCZ DDRII(533mhz) hdd: WD 250gb SATA Maxtor 40gb ATA Video: ATI x700 PCI-e Sound:Integrated into mobo Case: Antec Sonata PSW: 450W Antec I switched my video card to the ATI 1900GT and the flashing no longers occurs.