Thermal Pads: Does higher #w/mk mean better? (Not on the die, on the heatsink)

So I'm talking about the pads that are put on the heatsink or GPU surrounding the die. I saw many kinds and the biggest difference in price seemed to stem from higher #w/mk = more expensive.

Basically, how do you choose the right thermal pads to put around the GPU/Heatsink? I use TIM on the actual die.

 

Can you estimate how far the heatsink is off from the VRAMs?

 

Higher W/mK means better heat transfer.
When choosing thermal pads, you should also take their original thickness into account.
As for the die, thermal paste will always be better.

 

I got about the same thickness I suppose (at least from what I could feel/tell.) I ask because I replaced some of the ones that originally came with the laptop when I repasted my GPU and when I went to buy more pads, I noticed that there were other, more expensive ones. I wasn't sure it was worth spending 25 dollars on one that said it had 25w/mk (the 4 dollar ones I bought were 4w/mk.)

Although my temps atm are good, I think I need to replace the thermal pads because I didn't know that you shouldn't touch them as you place them (I pressed hard on them in an attempt to secure them via "suction/stickiness" to the heatsink to make sure they didn't fall out of place as I put the heatsink back in place.) I read that touching the thermal pads is very bad (I probably left a slight finger imprint on it.)

 

Alot will depend on the spacing between the heatsink and GPU it sits on. I do know from experience I found a dime will fit between the heatsink for a DV6000 heatsink and I used thermal paste between it and the GPU and heatsink to a dime(US) size space and found it works and kept the laptop from dying and wow it did keep the GPU from dying or shutting down the laptop should they push the GPU. But this fix only works if the GPU hasn't haded the dreaded Nvidia dead GPU problem so we caught it in time to preserve and keep the laptop running still. I removed alot of thermal pads and replace it with silver thermal paste where I could and that helps improve heat cooling alot better. Another example was my M-6860 that I replaced the thermal pad and they melted just from running not from game usage and caused sudden shutdown and so I alcohol cleaned the GPU and applied silver thermal paste and haven't looked back although that heat sink can now produce heat that to me is a sign it is working properly and no more shutdowns. But since my nephew has it now I just hope he takes care of it.

 

Yikes... melting thermal pads do sound scary, and it's one of the things I'm worried about (with my GPU going to 83 degrees max when being OC'ed.) Everything seems okay temperature and function-wise though (no random shutdowns, temperatures are in a good range) so if problems start or I feel the need to repaste I won't be touching the innards of my GPU for a while (unless you guys think the whole "touching the thermal pads with my fingers and leaving slight finger marks on them" are reason enough to change it?)

 

Some heatsinks/chassis designs don't allow for thermal paste/non standard thermal pads, so also take that into account.

 

Well I couldn't really find a lot of info regarding thermal pads... a lot on thermal paste and what/how to use them on the CPU/GPU dies, but as for thermal pads... not much info. The one that my laptop originally shipped with were falling apart when I opened my laptop up, so I just tried to find something similar to it and just tried it. Seemed to work though...

 

Typically thermal pads are used when the contact metal can't touch a component, which usually occurs with VRAMs and VRMs, rarely CPU/GPU. A standard thermal paste with little or no pressure will simply ooze out over time, depending on its viscosity. Thermal pads usually don't do that.

 

In most cases where you have a thermal pad you can replace it with a copper spacer and you'll get much better heat transfer, but usually where you find thermal pads, whatever they're filling gaps for won't get too hot anyway, outside of VRMs.

I've had to replace the thermal pad on my northbridge because it was melted through and was running into 80c doing absolutely nothing, swapped it with a copper spacer and no issues since.

If you get a thick enough paste, you don't even need the pads, but this depends on how much space is in between the heatsink mount plate and whatever its supposed to cool.

 

I would avoid the electrical conductive pastes if you really want to use the paste methods for wide-gaps, since there wouldn't be any pressure to hold them in place.