Thermal pads?

Merlin5 · 28 May 2015 at 12:57

Hi guys. I took my Dell Vostro 3550 laptop apart last september right down to removing the motherboard, and I put thermal paste on the CPU and GPU, having first cleaned the old factory gunk off and rubbing down with isopropyl alcohol.

Temps were way better after that but recently they've been getting very high during gaming or watching videos. Idle is not too bad, usually around 50c, but under load, I'm getting a bunch of artifacting on screen and often bluescreening followed by rebooting itself. Even my coolermaster cooling pad with twin fans isn't helping much anymore.

So I plan to take it apart again and redo it. What I want to know is, should I replace these heatsink thermal pads that I've marked with yellow? They're the old original ones that I stuck down again. Could they be the problem here? And where do I get some? They look like they're over 1mm thick.

Also, you can see the blobs of Arctic Cooling MX-2 that I put on. Is that too much or about right? I tried to put it together again as straight to make the paste squish out evenly but for all I know might have not made a perfect seal.

My MX-2 is from august 2009, there's loads left but it's now almost 6 years old. Time to replace it or can I still use it?

Regarding the whole fan/heatsink assembly,

I can hear the fan spinning up under load, so I presume it's working properly? I considered buying a new one but can only find used anyway which I wouldn't really trust.

MOOGLEYS · 28 May 2015 at 13:43

You want about the size of a grain of rice for paste. It looks like you used quite a bit in the pics. The pads can be re-used but if they are splitting or looking worse for wear it's worth replacing them whilst you have it in bits.

Merlin5 · 28 May 2015 at 13:54

MOOGLEYS said:
You want about the size of a grain of rice for paste. It looks like you used quite a bit in the pics. The pads can be re-used but if they are splitting or looking worse for wear it's worth replacing them whilst you have it in bits.

Yeah, I'll use less next time. Is it still good to use though at 6 years old?

I just checked a video and there's some stuff called K5 Pro which comes in a tub as a viscous thermal paste to use on vram chips as an alternative to cutting strips of thermal pad. Demonstrated here,
https://www.youtube.com/watch?v=e9v5MDivZfc

What do you reckon? Thermal conductivity K>4W/mC

Is that good? But I know there are more expensive thermal pads at 7W thermal conductivity.

Meaker · 28 May 2015 at 18:01

You can improve cooling by using thinner pads if the mounting allows. Don't paste it, get a 0.5mm strip and 1 mm strip and see if 1 mm makes contact, if not stack the 0.5mm on top (large contact area means this works fine). Any standard 5w/mk pad should do nicely.

Merlin5 · 28 May 2015 at 18:33

Meaker said:
You can improve cooling by using thinner pads if the mounting allows. Don't paste it, get a 0.5mm strip and 1 mm strip and see if 1 mm makes contact, if not stack the 0.5mm on top (large contact area means this works fine). Any standard 5w/mk pad should do nicely.

OCuK have a JunPus JP-P600 High Performance Thermal Pad 100x100mm x 0.5mm and the same again in 1mm, but they're both over £10 each. And the 0.5mm is out of stock. Is that what I should be paying for thermal pads? Good thermal conductivity though at 6W/mK.