CPU idle's around 37 then shoots up to 90c when playing taxing games

[willeystyle]

ok so a couple of months ago i removed the thermal pad from my intel q8400 and replaced it with arctic silver 5 thermal paste cause i was told is was much better so i turn my comp on the idle temps are fine in core temp highest core temp was 41 so i tested it with MW2 also i would like to add my failsafe on core temp is 90c i played for like 15min then my computer shut down do to over heating i followed arctic silvers instructions i dont know what i did wrong here's my Comp stats

OS:Windows 7 ultimate 64-bit
Mother bored:Gigabyte G41M-ES2L
Processor:Intel core 2 Quad Q8400 @ 2.66GHz
Memory: 4 gigs of DDR2 800mhz
Video Card: Nvidia Geforce 9800gtx+

[Kurtiskain]

I can only imagine there would be too much thermal paste on there. Too much, in my experience, is worse than none.
The other option is that one of the retentsion clips for the heatsink is not clipped down correctly.

How much thermal paste did you apply to the cpu?

[willeystyle]

I fixed it the fan was not clipped all the way down  thanks