Ok this printer of yours, is it hooked up to the same power-outlet as your computer and other devices?
What it looks like, something is drawing power away from your monitor. I would suggest to take your printer and plug it into another wall socket and see if you still get these random cut-offs.
Otherwise, i am not really sure what could be causing this...i don't think a printer would interfere with a video card
Desktop - DualBoot: Fedora 15/Windows 7 64bit
Netbook - Windows 7 Professional
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