Alienware 17 - Performance Hick-Ups / Drastic CPU usage differences

Dear all

I am not sure since when this problem occurred exactly but it must have been recently. 

Since a couple of weeks my Alienware 17 suffers from, what I can best describe only as, performance hick-ups. The situation is as follows:

I play a game which is more or less graphic intensive like Skyrim, L.A. Noire, Fallout 3, Witcher 2. The game seems to run complete smoothly, no framerate drops what so ever. But then suddenly the game starts to lag. In the same moment I can hear my fans go faster. This sequence takes about 30-60 seconds, than the fan slow down again and the game runs normal again. Problem is, that happens every 3 minutes and make playing games difficult. Even putting any of the said games on the lowest graphic settings doesnt make a difference.

In an attempt to fix the problem I bought a special cooling pad for laptops as I at first suspected some sort of overheating but still, the problem remains. The fans were cleaned too...

Further inspection reviled that during the time the fan speed goes up, the currently executed game loses about 10 -15 % CPU usage of which it recovers as soon as the fan speed lowers.

As soon as it is up with the CPU usage again the game runs fine until it arbitrarily takes does CPU % down again.

Hence I closed all programs I had in the background, only having my game open but still, no success.

I am at the end with my English and hope someone here can give me a good tip on how to fix this issue.

If required, my system has the following CPU installed: Inte i7-4910MQ @ 2.90 GHz

And the following graphics card: Geforce GTX 880M

All drivers are up to date.

Thank you very much.