Due to the recent hot summer temperatures, it seems like my video card is overheating a bit. My screen freezes randomly whenever I play games or even just playing video. I can hear my Video card rebooting when the screen freezes. There wasn't a problem during the last 2 summers. I think the thermal compound isn't working properly.

So I assume it's a heat transfer issue. So with all of RS' expertise, I need to know which thermal compound is decent/good enough yet moderately priced. Around 10-15 bucks or less.
If you're wondering what temperatures are for my GPU (x1900GT). I'm currently using a Desk fan to cool my videocard. LOL. It's hovering around 58 degrees C with a Fan speed of 41%. Seems a bit high.
Thanks in advance! (I wish i had AC lol)