Blury graphics and text

On my desktop, I've been having troubles running games, my gfx card would just turn idle and the screen would turn off. I then for some reason started to experience blurry text and out of focus graphics. When i used the auto focus button on my LCD screen, the whole screen would be displaced to the left by a couple of CMs.

This is what i did, it solved the problem but which attempt solved it? no idea

• Turn the resoultion down and then back up in Windows XP
• Turned off tower and monitor for a while
• Disconnected monitor cable from gfx card
• Used a paint brush and clean dust off card
• Re-connected cable and gfx card to tower
• Powered back on, all fine again :D

My ideas are maybe lose cable, and after cleaning i put it back on tighter or turning off the tower cleared something maybe? OR last explanation would be faires or nothing, just time fixed it {shrugs}