Security app you all use and is it in a browser window?

Wild guess: Are all the effected PC's on the same UPS, surge protector or AC supply line/breaker?

 If so, have an electrician check your  buildings electrical system out or at least the supply to the rigs in question.

Wild guess number two:  Do you or the others have unshielded speakers near the monitors?

Nope, not overheating Kitkun, both cards running at around 99 degrees Fahrenheit (38 degrees Celsius) or less at times.  Even when my son plays an intensive game the primary video card only goes up to 112 degrees Fahrenheit.

yrag: Not in browser. The PC screen just flashes as if the video drivers were going crazy. I guess the best way to describe it is it looks like someone taking a picture of my screen from the inside.

Lightstar: minde doesn't go black, it just flickers, flashes.

Wizard: not sure about a UPS, I don't have one on my PC as it's connected to the plugs built in to my cubicle where there are 6 PCs connected but doesn't mean there isn't one for my row. It's possible, however I have seen individual UPS's in some cubicles around me. No speakers on my desktop, only headphones and the speaker built into the PC case. It's a Dell PC with XP.

Kitkun: Flash, like a picture flash. Or flicker.

Uvah: I guess it is a cool avatar, can't see the whole thing though thanks to JU's style of showing enlarged versions in the comments where you can only see a piece of it.

I said the same thing but used one more  r and one less ' .

It could be lots of things, including EMF, stray RF, line noise, even a microwave heating up a pizza nearby. 

CharlesCS, are all the affected PC's in your cubicle group?

Until now, I've never felt a need to copy, print and frame a forum reply.

I'm not sure what you edited. I was referring to the fact that you and Jafo agreed on something.

 As for feeling warm and fuzzy, we have threee cats for that, all warm and all fuzzy.

BTW Dumbass: We saw your reference in  # 3. Unfortunately, both Jafo and I are incapable of reading anything misspelled........

Fortunately, Jafo is capable of posting misspelling, he's just very fast at correcting it and his edits won't show.

BTW: I answer to Smartass to avoid confusion with any nearby dumbasses.

@ CharlesCS. If you can get an AC line filter for your workstation and try it, or plug the microwave into a different circuit, it might help you out if it's line noise. If it's stray RF you may be out of luck unless the microwave can be moved or replaced with one with better shielding.

P.S. There is no misspelling in reply #3 but thanks for checking.

Yes there is.......

lmmfao

Yep...

l-my-mother-f-a-o

Fuck. Now he's correcting abbreviations.