does the video look when this when you first start the computer up? can you can the bios screen and the logo? and does it just do it in windows. also if you have pci-e card anykind will work or pci video card put it in and see if you get the same problem if you do. it might be the cpu but i think it is the video card
This occurs only after the machine's been running a while, no set pattern - sometimes quick, sometimes takes a long time. Generally at least once a day, maybe more.
This never occurs during startup, only after some variable period of time. The machine temps are consistently ok.
We are only running windows, so I can't try otherwise. Actually I have linux on a USB somewhere, I'll check that out -great idea.
My plan has been to find a PCI card and try it, and I just need to do it. I am convinced this will solve it, I just have to get on with it.
Thanks all - I'll let you know