E6420 Overheating, Questions About Repair

Hello again everyone. I have an E6420 and it's overheating. However, I think I may have caused the issue myself. Here is the order of events that happened:

When troubleshooting an unrelated issue, I thought the CPU may need to have the thermal compound redone. I tried everything else, so why not? So I cleaned off the existing compound from the CPU, GPU and Heatsink, and applied some trusty artic silver on it.

I noticed right away my idle temperature dropped 15-20 degrees. It was idling at 80F. Awesome!

A few hours later, the idle temperature increased to about 15-20 degrees more than normal. It was idling around 130-140F.

A technician came in to try to fix my "buzzing" sound (a separate issue, separate topic) and he offered to "regrease" the CPU for me. By the time he got done with it, it was overheating so bad that it wouldn't stay on for a full minute before shutting itself off. (The technician used thin thermal strips). I got mad and sent him on his way. I decided to fix it myself. He gave me samples of the thermal paste that Dell gives out.

I applied the thermal paste after cleaning it, and the same thing happened, it initially was much cooler, but later on it got much warmer. I caught it running at 200F at one point.

So here are my questions:

1.) In regards to the thin thermal strips, the one the guy used that made it so hot it couldn't turn on, what are the purpose of those?

2.) What is recommended, Dell's thin thermal strips, or their paste? Maybe the thin strips were applied wrong?

3.) Based on what I said, maybe I'm putting too much or too little thermal compound? In my entire career I've never once had an issue with this. I've re-applied thermal compound many times before without incident. But ever since I decided to re-apply the compound on this machine, it's been horrible. I should have left it alone!

Please note: I could call Dell and have them send someone again, but I'm tired of that and decided to make this repair myself.

 

1)What is the puropose of using thermal strips ? Is it what you want to ask about ?
2)It is recommended to stay away from Dells stuff. Use Arctic Silver 5(CPU) and Phobya XT 7W/mK thermal pad(s) where necessary (i dont know yor config) Choose the right thickness of them. Remember to clean everything with IPA before applying.
3)Better check the clamp of cooling system.

 

1.) I was mainly wondering what their purpose is vs the liquid compound.

2.) I have Arctic Alumina, is that similar? Are you saying I should use Arctic Silver AND the pads, or just one or the other? If I use compound, how much should I be using? I normally use a drop about a third the size of the core any other time I've done this.

3.) There isn't a clamp, but five screws.

 

I haven't worked on the E6420, but with most systems, Dell uses thermal grease for the CPU and thermal pads for the GPU and chipset. Assuming that's the case with the E6420, I would guess that the GPU isn't making contact with the heatsink. Did you remove any thermal pads? If so, you need to replace it with a thermal pad because the gap is too big for grease.

Arctic Alumina isn't as good as Arctic Silver 5, but both are better than the OEM grease or strips. I always replace OEM grease with Arctic Silver 5, but unless you have better pads, I would just leave the pads alone.

 

Thank you. Unless I'm not looking at it right, it doesn't appear that the GPU is overheating. The CPU is where I'm seeing the problem. No, there were no thermal pads on the CPU or GPU prior. There is a really ugly thermal pad on another chip that is not the CPU or GPU. Not sure what it is.

 

It's probably a thermal pad for the chipset. Have you removed the heatsink and inspected the grease? Make sure it has spread evenly and isn't too thick.

What technique are you using for application? Did you spread it out with a credit card, or put a drop in the center?

 

I put a drop in the center. I didn't spread it. About how much is "just right" so I can make sure I didn't overdo it? I may buy some arctic silver 5 tomorrow.

 

For notebooks, I always spread it with a credit card to make sure that the entire surface is covered (when the drop of grease is compressed, it will form a circle, which isn't what you want). Putting a blob or line of grease is better for larger surfaces (such as desktop CPUs).

Try this: After you clean and prep, use Scotch tape to mask off the rest of the CPU. Put a small drop of grease on the center, and use a clean credit card (if you can cut it to 1/3 the width, that would be even better) to spread the grease. Get it as thin as possible, yet enough so that surface is covered. Make sure to remove the tape before reinstalling the heatsink!

 

Thanks, I'll try that tomorrow.

 

Let me know how it goes. Make sure the GPU is making contact though (take a look at the heatsink when you remove it to replace the grease, that way you won't disturb the newly applied grease), I just checked eBay and it looks like the GPU may have been using a thermal pad.

https://s3.amazonaws.com/HTFN/HTFN-00210-2.JPG