Since the MX 440 works I think that the faulty socket can be ruled out though

Okay, thanks a lot for everyones help.

One more thing though...today I plugged in a printer, and as I was pushing it into the back of my pc, I got a 'no screen found' error message and it went into standby, forcing me to restart. So I rebooted into safe mode, but now there is some kind of weird red/white dot matrix thing over most of the screen, and a little square of it follows the mouse.

This kind of leads me to believe it might just be the cable connecting monitor and card, some kind of broken pin or whatever goes wrong with them. Views?

Or broken solder joint or dry solder joint on the graphics card if you wiggle the video lead at the video card connection will the picture change?