Thermal paste drying out

[leclod]

I'm sceptical about the subject thermal paste drying out. The oil contained in the paste isn't the element carrying the heat.

 

Yesterday I replaced a fan in my MSI RTX 3070 Duo, I also repasted and repadded (it's not easy).

Temperatures lowered under load by 8° (for now).

 

But I was surprised to see the pcb is only connected to the heatsink via 4 screws around the die, like on my previous 3060 mini.

So there's some play in that connection. Each time I plug and unplug the 2 pcie power connectors, the pcb will rotate slightly in regard to the heatsink.

Those connectors do require a significant amount of force and this will continuously weaken the thermal bond between die and heatsink.

(I'd like the thermal pads to help securing both parts but I'm really not sure, those didn't seem to form a strong bond)

Edit : No you fool ! plugging unplugging doesn't exert any force on the heatsink so it shouldn't move in regard to the PCB. Sorry guys, false alarm.

 

This seems to me a much better culprit for temperature degradation over time than thermal paste drying out, except of course if one never changes his hardware.

Edited May 28, 2025 by leclod

[Mark Kaine]

My 3070 still got same temps after 5 years and like 12+ hours of daily usage... So I'm also skeptical about paste drying out, but at some point it probably does... was checking on my old AMD 64x2 recently and the paste wasn't dry... It was just mostly gone lol (the remains looked weirdly watery, not dry at all)

 

[leclod]

5 minutes ago, Mark Kaine said:

So I'm also skeptical about paste drying out, but at some point it probably does...

No no, thermal paste does dry out.

I just think it doesn't really matter because the oil that vanishes wasn't the important element in the first place.