HP8510p - replacing thermal paste

Hi, I've had this lovely 8510p for a few years, and for the past few months the CPU temp has been ~10C higher than it used to be. I regularly clean the fan compartment of dust, so it wasn't that.

It used to idle at around 30C, recently it's been around 40C. So I thought perhaps replacing the ageing thermal paste would help. I took off the kbd and the head sink, noticing the existing thermal stuff was indeed a bit crumbly. Cleaned the 3 pasted areas with alcohol till they were clean and shiny (both heatsink and chips), applied some Arctic Silver 5, put it together and turned it on.

Now the temp idles around 47-50C! I must have done something wrong. It's summer here, room temp is about 30C if that makes a difference. The fan is working fine.

I've only ever done this when putting a PC together, so not sure if lappy chips have particular pasting needs. The coat of AS5 wasn't thick, and only applied to the small square on top of each chip. Slightly more paste as you'd butter a slice of bread with. I tried to make it smooth, avoiding air bubbles.

Is there any particular advice someone can give me about applying thermal paste in laptops which might improve what I've done? I can take it all off again and take a photo if that would help. It just seems I could have done a better job here, as it's never idled at such a high temperature before. 50C (60C under load/gaming) is much higher than it used to be.

Thanks for any advice!

 

The coat of AS5 should be thin, not thick. The amount to put on the heatspreader should be about the size of a grain of rice.

 

Thanks 2.0, that's great. The existing stuff was very thick so I went the in-between route. I'll redo it this afternoon and see how it goes. Cheers!