CPU Temperature question

Hey everyone,

I recently installed a giant CPU heatsink (OCZ Vindicator), using arctic freeze thermal paste. I'm confident I installed it right; thin even layer on thermal paste, installed tightly, etc. I have a 120 mm intake, which blows right onto the heatsink, then an 120mm exhaust fan on the side.

The idle temp is really nice, 35 degrees and neither fan runs. Soon as I do something CPU intensive (defrag, games, etc.,) the temperature very quickly rises to 70 degrees and I've seen it peak near 75 degrees. I'm very concerned and am wondering what is causing this, or if I should be concerned at all.

Moderate activity (internet, MSN, torrenting) only raises it to about 40-50 degrees. Thanks for any input.

Oh, system specs might help:

Geforce 7600gt
915 Neo-Pl mobo
2 gigs of standard ram
Intel pentium 4 2.6ghz
X-fi gamer sound card
Windows XP

Using speefan to monitor temp

I would try a different heatsink... it takes very little thermal paste...

it sounds like the heatsink is installed wrong, there should be very very little thermal paste on it, just enough to cover, not a but more, no globs, put a tiny bit on and spread it as much as possible

second, and most important, it must be tight, very very tight, when you put the heatsink on you should be worrying about breaking something, force should be required, if it just slips into place without work then you did it wrong. After its installed hold the heatsink and try to move it, it should feel firmly bolted to the motherboard, moving the heatsink should always move/bend the motherboard, nothing should rattle, it should not be able to move off the CPU at all.

If you have a very thin layer of paste and the heatsink is on very tight and your still having problems then you can start thinking about other things (maybe the heatsink is too small, what one is it?)

I think you should consider the air circulation also, whether your fan blows correctly. The air inside your box must be replaced with cooler air from outside.

AmericanChopper is right about air cirulation. You should always have cool air intake from the front case or side and a out take of hot air in the rear. Also note that the room temp has a lot to do with the temp inside of your case and hence the cpu temp also will go up if warm air is being suck in and hot air being suck out.