Video card overheating at stock settings!??

Hi guys, I just got this MSI 8600GT a week ago from newegg:

MSI NX8600GT Twin Turbo GeForce 8600GT 256MB 128-bit GDDR3 PCI Express x16

The problem I've got is that during Counterstrike Source and Oblivion the monitor might flash black every minute or two. I changed from a regular LCD to an HD-TV LCD and it flashes less, but still happens. Decreasing the resolution and game settings SEEMS to lessen the flashing as well. Also, Oblivion has minimized to the desktop several times mid-game.

Did I get a bum card that I need to return?? I only have one 120mm fan in the back of my case, do you think some simple case fans should fix the problem? God FORBID I actually use the "turbo" shader overclocking button... it froze my entire system after about half an hour of gaming.

AAAAHHHG!!! I'm very frustrated with Nvidia or MSI, whoever's fault this is. Any insight on what the hell is going on is MUCH appreciated!!

550 Watt Antec Truepower
Athlon 64 5600
2 gigs pc6400
ECS Nforce Mobo
latest online drivers, and windows xp

Also HDMI wouldn't send a signal to the HD-LCD, but that's another problem for another day... I care about freezing and blinking and minimizing a lot more.

Ok... Keep an eye on your GPU tepmerature next time you play either of those games and post back what the maximum temperature is. Also post back what the temperature is AROUND the time that it blacks out. It could be a simple matter of not enough air flow. Only 1 fan you say... Jeez no wonder