CPU Temp Skyrocket

My CPU goes from 50 degree to 100 degree when i start guildwars.
If i play other games my cpu acts normal.

Specs :

e8400 not overclocked stock intel cooler
asus p5q MB
600W Recom PSU

Any Ideas on how to solve this?

Its a cpu and yes i used everest ultimate to check the temps
the problem was the heatsink wasnt connected very well

bought a new cooler cpu is 25 degree now

What method of temperature reading are you using? Some are more reliable than others (Coretemp, for example) - because any processor worth it's salt would shut down at those temps.

Are you getting any performance issues/random shutdowns etc.? If not, I would assume a mis-reading. If not, try cleaning all the crap out of the fans and case interior with a few blasts from an air can. If it still persists, you may need to think about a better HSF with a nice layer of AS5.

There's a few puzzling things i see here. For starters,
You're sure that's a CPU reading and not GPU? GPU's can handle those temps(barely) but a CPU would fizzle and fry up long before 100C

Other games such as Solitaire? Couldve sworn the little stress GW puts on your computer went mostly through the videocard but maybe thats becuase i game at high resolution.

At any rate it seems the connection between your*Very late Edit:this goes for GPU as well* Heatsink and CPU has been lost(Suddenly temps skyrocket like so) or you have lots of dust built up in the heatsinks fins(temps would steadily get higher and higher over a longer period of time). So as Snoggy suggest get a can of compressed air and blow it out the best you can, then download a trusted program and retest your temps.

If nothing has changed you might need to remove your heatsink and re-apply some Artic Silver 5.
I cant think of any other reasons unless you were fiddling around inside the case,temps would do this.

sure does sounds like a GPU to me too.

Blow the dust out of it and then download Everest Ultimate to check all your vital temps.