Thermal grease application help

So after my thread I posted about my laptop throttling all the time I got some Artic Silver thermal paste and I've vacuumed out the copper heatsink (there wasn't much dust).

Now I have a few questions if someone doesn't mind helping. For one thing since my computer is a laptop, the heatsink it came with had sticky pads that were attached to it and you peeled off stickers and then pressed the heatsink onto the CPU, the GPU, and some other component that I'm not sure what it is. Well now that I've removed the heatsink, I see that the sticky pad over the CPU has completely melted into a big mess, which may explain my throttling problems. So to this I just add a pea size drop of thermal paste right? Now for the GPU and the other component, their sticky pads still look new. Should I just leave these alone and reattach the heatsink, should I add thermal grease between the pads and the heatsink, or should I strip the pads away and apply pure thermal paste?

Thanks!

 

It's one or the other. If you're using AS, clean everything off thoroughly. There are plenty of instructions on proper application technique, but I should warn you that you can't simply take the pads off and just replace with paste. You may need a shim to span the gap created by the lack of thermal pad. I don't know what model laptop you have, so I can't say whether you need one or not. AS cannot be used to fill that gap. You will destroy the chip.

 

The other component is probably the northbridge chipset. The CPU itself should not have a "sticky" pad. These are thermal pads and are never ever placed directly over CPU dies. They should also not be peeled off. They are used for memory, chipset and other ICs and power components where paste is not applicable. Take a picture, that will allow people here to give you some advice.

 

They absolutely are used on CPUs and GPUs. Every Dell laptop I've worked on has had one, as have the netbooks I've used. Maybe you're thinking of thermal tape? Pads are used with screw-down/fixed heatsinks. Tape where it's not locked down (RAM, IC, NB)

 

I stand corrected. When I think of pads I think of the thick squishy stuff they use on ram chips. I've never seen this on a cpu heatsink.

 

Yeah, the CPU did originally have a pad, however, it melted away into quite a mess, so I rubbed it all off with alcohol and put thermal grease instead. I went ahead and did that before I read woofer00's post on how I should have something to bridge the gap where the pad was, but I went ahead and booted, and I either put enough paste or screwed the heatsink on tight enough that there no longer seems to be any throttling problems. Previously, my CPU would reach 100 degrees Celsius running Prime95 and then shut off (or throttle when playing HD video), but now it peaks at 78 and doesn't throttle, so I assume it is working. I will keep monitoring it though...

 

What kind of cpu is it anyway? One thing you can do is remove the heatsink to see if the paste is spreading well across the die. If it's not, then a copper shim will do the trick.

 

It's a T7700. It seems to be dissipating heat pretty well right now, and I'm hesitant to disassemble it again because it takes like an hour and a half, and I always seem to crack the laptop case a little more each time...

 

Here is a great video showing the effects of different thermal paste application techniques...its sums up why you should always dot/line it, and never spread it.

YouTube - How Thermal Compound Spreads

As far a pads...ridiculous. No CPU should ever be bridged by a thermal pad. It shoud be CPU/paste/heatsink metal. Pads are for much cooler and less heat sensitive parts...

 

I purchased a nice piece of copper sheet a local hobby store, they had a great supply. I cut it to size, smoothed the edges and placed it on the northrbridge with some compound on both sides. I installed the heatsink temporarily, then removed it and everything made nice solid contact.