Adding some kind of heat paste when replacing thermal pads GPU and other chips

Question

My laptop's (Dell Studio 1555) CPU is getting quite hot lately (high 80 to low 90 degree Celsius). As a consequence the fan is blowing quite hard when watching HD video's or doing computational intensive tasks. Someone suggested me to replace the thermal paste and pads.

I opened up my laptop and saw that the CPU had grayish thermal paste on it and the GPU plus some other chips had a thermal pad on them. However, I also noticed some greasy transparent stuff on the chips where the thermal pads were. Especially on the GPU it seemed that some of this extra stuff was applied, since it was all around the GPU chip and not just on top of it.

After some research I found that for normal users (not the overclocking kind) it is sufficient to replace the paste with paste and the pads with pads. I also read not to use both of them at the same time.

Now I'm wondering what the stuff is on my chips which have a thermal pad. Does this greasy transparent stuff come out naturally, after prolonged use of the thermal pads (~6 years)? Or did Dell apply some kind of thermal paste, in conjunction with the thermal pads?

Answer 1

Forgot to take the picture again. But it looks as if it was some epoxy to glue the chip to the plate. It did not come off when I cleaned the chips with alcohol.