ENVY 17 3D - overheating, no surprise, but suddenly CPU does excessively

since HP has really managed to kill the envy line and merge it with the pavillion dv line, branding low quality poor hardware pavillions envy, i am still using my old, real envy 17 3d 1195ea aside from the brilliant elitebook workstations, because its only capable successor, the 17 3200 line, isnt available for purchase anymore, and anything newer (envy j#### line) is low-mid-end consumer crap.

now that the envy 1000 line overheats as soon as it is powered on is no news, i have been able to manage it quite well by opening it up monthly and cleaning it inside, even repasted the GPU & CPU some 3 months ago, which made the temps decrease by 10 degrees generally.

however since several weeks i am experiencing some really strange and excessive CPU overheating (although the 5850m GPU was the one overheating mostly firs until now).

it idles at 65-85, but with each burst (happening several times in a second), it reaches 99-100 degrees for a fraction of a second. ie. the temps jump constantly up to 100.

firing up something really stressing, as a game (CS:GO - since its cpu bound) or an app stressing the CPU, makes the CPU reach 100 degrees within less than 1-2 mins, leading to heavy throttling and ergo major performance hits.

even heavily GPU-bound games keep the GPU at 90-95 degrees (from my experience in the past, during bad times the GPU starts throttling at 104 degrees, so no issue at all), while the CPU gets up to 100 and throttles.


now my question - is the only explanation for this that the thermal paste became dysfunctional? ie. repasting it would solve it?

or can anything else be the reason for this?

thanks