delidding Temperature increased after Delidding?

[Husky]

Hi all,

 

I have an Intel Core i7 6700K that is cooled by a Corsair H110i GTX AIO. I decided to delid it as it was running at 95C with only a very mild overclock.

 

After delidding, I cleaned up all the black sealant around the edges until it was perfectly clean with no traces left, and then I applied some thermal paste to the bare die, then put the heatspreader loosely on top (just floating) and then reinstalled the CPU like that into my PC.

 

After this, I was absolutely blown away and really impressed, temps dropped from 95C to only 55C or so, same overclock settings, nothing changed except delidding. But then slowly, day by day, the temps got worse and crept up to the point where they are hitting 100C and the CPU is thermal throttling. I then removed the CPU, cleaned it, reapplied the thermal paste on the die, and the temps were good again. But then the same thing happened after a few days, temps got worse until it literally hits 100C and throttles just from dragging a window around.

 

I have tried a bunch of different thermal pastes and all of them have this effect. I had actually repasted my GPU a few months prior and that has been perfectly fine, the temps on my GPU improved drastically and have stayed that way.

 

I have a feeling that I am a victim of thermal paste "pump-out" but I am not 100% sure. The same thing happens if I lie the PC flat horizontally on my desk instead of vertically.

 

Is this a known thing? Am I supposed to lap something, or use liquid metal instead? Is there a special application method or paste I must use?

[For Science!]

38 minutes ago, Husky said:

 

Knowing the thermal paste would be good, but generally this should not happen. Perhaps the mounting pressure is too low. Photos of your application process may be helpful too, With direct die you should cover the entire surface of the die and not just a dot/line.

 

You should not need to lap to reap the benefits of a stable delid.

[Jeppes]

Liquid metal is better as no pump out with that.

[Husky]

8 hours ago, For Science! said:

Knowing the thermal paste would be good, but generally this should not happen. Perhaps the mounting pressure is too low. Photos of your application process may be helpful too, With direct die you should cover the entire surface of the die and not just a dot/line.

 

You should not need to lap to reap the benefits of a stable delid.

I have tried 3 thermal pastes: Cooler Master generic white paste, Corsair TMX40 and Phanteks PH-NDC_02 Nano Diamond thermal paste. All 3 of them exhibited the same behavior over time. The best performing one has been the Phanteks, was also the same one I used for the GPU which is working perfectly fine.

 

I am not sure about the mounting pressure. My cooler's screw stop dead at a certain point and refuse to tighten past that, so I think that's by design. I can experiment a bit by putting additional pressure on it with my hand just as a test.

 

I did not spread out the paste, I used a line over the die and when I put the IHS back on it smushed it over the entire die. I will try to spread it out and see if that makes a difference, but I am not sure since I used the line method for my GPU as well and that has been fine.

 

I agree that I shouldn't have to lap. If all else fails and I can't get it sorted out, then I will try lapping it just for the hell of it. I've already come this far with delidding, what's a bit of lapping gonna do to me?  Thank you for your help, I will try your suggestions and will send some photos when I do this again.

[Husky]

8 hours ago, Jeppes said:

Liquid metal is better as no pump out with that.

I have heard this a few times, and I have seen that most people who delid their CPUs go for liquid metal so I am inclined to do the same now. My only concern is it's longevity. I am worried that it will eat into the IHS or something.

[For Science!]

9 minutes ago, Husky said:

I have heard this a few times, and I have seen that most people who delid their CPUs go for liquid metal so I am inclined to do the same now. My only concern is it's longevity. I am worried that it will eat into the IHS or something.

It will only amalgamate into the IHS if you lap the underside, nickel is a decent barrier for liquid metal. 

[WoodenMarker]

Seems like normal pump out. Use liquid metal instead. 

[Husky]

Alright thanks everyone, I will first try a slightly different paste application method, and if that fails again, then I will get some liquid metal and try that. Hopefully it resolves the issue!