white stripes (the wrong kind)

Recently I 've bought a Radeon HD 7850 with GB RAM. It worked splendid until yesterday, a few hours after installing Fedora 19 in a dual boot with windows 7. When it suddenly started showing me white stripes in windows and today I noticed snow in Fedora . Could this have to do with the fact that I tried installing my drivers in Fedora or that my dad cleaned my desktop case with a (not very) wet rag

 

Cleaned case inside or youside? If video card is contacted with wet rag, it may cause it to broke.

 

Boot up into Windows 7 to see if it does the same there...It is probably just linux..

 

I had problems in both windows and linux, but it vanished now, probably water that dried up now?

 

Prehaps but that can cause problems later.

 

you were right, I have the same problem again now. But it only started after my pc was on for about 4 hours. Could it be an overheating problem maybe, even though I didn't play any games yet?

 

What kind of case do you have? And how many fans are in your case?

 

solved, it's stupid but it turns out my HDMI cable was not completely plugged in