help please, computer freezing after playing game for 10 min

i have a 6600gt made by evga inside a sony vaio pcv-rz32g, with a gig of ram added in. lately whenever i play a game that is ran off of directx9 my whole computer just stops loading. does any1 know how to fix this? i have tried to reinstall drivers i have reinstalled windows, i have done all i can think of but it still freezes, am i going to have to get a new graphics card? i dont have much money for one because i am getting a custom guitar next month so do you guys think i should try and get one off of ebay or something?

That's not the original graphics card is it?
It's monster of wattage, and it really strains just about any sub 300w psu.
It's very likely the PSU if you upgraded your GFX recently.

Could be overheating, or maybe dying RAM... or dying PSU even

Both are easy to check:

1. For the GPU temps, find out your GPU temp in the driver panel and tell us.
Also check CPU temps with motherboardmonitor or something, or even in the BIOS.

2. For system memory, run memtest and see if you get any errors.

3. For PSU, check the 3.3, 5, and 12v readings (also with motherboard monitor, or in the BIOS.

Let us know!

Table 6. Voltage Tolerances
Voltage Rail Tolerance
+5VDC ± 5 %
-5VDC (if used) ± 10 %
+12VDC ± 5 %
-12VDC ± 10 %
+3.3VDC ± 5 %
+5VSB ± 5 %

-----

Your 12 volt is way out of tolerances per the spec (vers 2.2. ATX). It is +~30% over which could very well be your problem. Your heat levels are not really of any concern as far as I can tell, CPU's and Video cards can get far hotter than that (especially video). ASsuming your RAM is not bad then I would go with the PSU; it is far more likely that the PSU went bad than the RAM going bad.