Graphics Card affecting new RAM stick..?

Okay so I just got a new stick of ram. PNY 1gb, upgrading from 256mb on my Emachines T3104. I got an Nvidia GeForce 7800 SLI Series about a year ago, and all of the sudden today it has been acting a little weird after having some complications with my stick of RAM. I have tried a memtest and cleaning out my case and video slots/card. I've been told it looks like a heating problem but my card has always been a stable 48-50. Today my machine was freezing before it loaded the windows xp loading screen, fixed that I believe with a new ribbon cable. Put in the stick of ram, and started working fine, and than I found out about the graphics. When I try to play a game, it looks like this.
http://i3.photobucket.com/albums/y83/Peppe...01/scrn0006.png

The other day it was working just fine, everything running smoothly and than today everything just goes wrong. I've updated my drivers and all, but I still see the same thing when I try to play any game. Can anyone tell me why? I don't get any beeps or errors when I boot up.

 

Your picture (link) don't work.....

 

http://i3.photobucket.com/albums/y83/Pepperman3001/scrn0006.png

 

how long did you run the memtest program ?

 

Until it finished, I didn't really pay attention to that..

 

Have you tried removing the RAM to see if things return to normal with it removed? Maybe try the RAM in another slot? Also check the video card; maybe you bumped it loose while installing the RAM or new ribbon cable. If the video card has its own power connector, make sure it's connected firmly. Lastly, maybe the RAM upgrade is drawing more power than the system was before and the power supply can't handle it (check ALL the power connections whilst in the case). If you have access to a stronger power supply, give it a shot. EMachine power supplies are notoriously low-end, so an upgrade in the PSU department is probably a REAL good idea. Be sure to unplug the main power cord each time BEFORE you get into the case. Leave it unplugged for about a minute to totally discharge before pulling RAM sticks and what not...

 

I i tried everything you suggested, I unplugged my second HDD and one of my disk drives, my PSU is 300 MAX. I checked the cables, switched out all ribbons. Still gives me same problem, it might be the RAM stick is not compatible with the motherboard but I also tried a different brand and all. Even with my original stick in their it gives me the problem..I tried a different video card and it gave me a beep of which im not sure as to why..>>