Graphics card or Motherboard problem?

[heatkl]

I had a 7800GT working fine on my computer but sometimes it would freeze my games and i would require a restart. I decided to RMA my card and the next one I got became worse. I had lines everywhere and windows would start and than it would go blank. To get it working I had to push down the front right corner of my graphics card for it to work properly. I decided to try out a 7600gt and it came up clear, but after 5-10 minutes it started having lines everywhere. I restarted my comp and my monitor was blank and couldnt connect with the graphics card. I held down the 7600gt on the front right side and pushed down and than my screen would show up. I had to do this everytime for it to work. Sometimes it will take several attempts of pushing the graphics card down for it to work. recently my windows boots with red green colorful lines everywhere. I took both graphics card to a friends house it came up with the same problem, but didnt have to push down on the graphics card on his comp. should i buy a new graphics card and see if it still works, or do i need to get a new mobo too?

My comp parts:
Asus A8N-E Mobo
antec 500watt
evga geforce 7800gt and 7600gt (both defected now)
amd ahtlon 3700+
2gb ocz ram

 

[Matthew DeCarlo]

Were the video cards known to be working fine before you installed them in that PC? If they were, I would try another motherboard, otherwise attempt whatever is most convenient for you.

 

[MrSnoobs]

silly question, but does the AGP/PCI-e slot have a sliding card lock on it? If so, make sure its being used.

Also, as above, use the motherboard as a variable: put the card in another PC. If it works, then its the mother board. If it doesnt, then its the card.