Is it possible to screw heatsink too tight?
I have replaced today thermal compound in my MacBook Pro after almost 5 years. I have noticed that temps have gone up about 5-10K. I've inspected heatsink and paste was evenly spread but very thin or even barely noticeable in the area which contacts CPU.
The question is - is it possible that I screwed heatsink too tight? I didn't use excessive force.
PS: the thermal compound I had at hand was cheap so I have already ordered Thermal Grizzly Kryonaut.
Update (06/19/2018)
Thanks for reply @arbaman
I'll update this thread when I get new compound tomorrow. I'll apply more paste this time to make sure there's perfect contact between heatsink and CPU.
Just quick thoughts:
1. When I used to build PCs, the amount I used to put was rice sized. I opted for the same size here on my first attempt and about 2 rice grains on second. I never spread compound and let the heatsink do the job.
2. Maybe thermal compound I had was old and deteriorated? It appeared thicker than usually. I used Titan Nano Grease. I usually use Arctic Silver or Kryonaut but I didn't have them at hand.
3. Maybe iStat Menu reports incorrect temperatures? Right after applying paste temperature was stuck at 80C after bootup (bootup uses all 4 cores at 100%). I have rebooted the computer and everything started working correctly.
4. Maybe I have some misconceptions about temps. I have to analyze iStat Menus charts again but I believe I used to have about 35C idle temps in normal mode and 50C idle in clamshell. Now I get about 50C idle both in clamshell and normal mode (today at 20C ambient it was about 45-50C idle in clamshell, and 50-60 as soon as I do anything light like browse web). Maybe I'm wrong about idle in normal mode? Now that I think about it 35C idle seems low considering iStat clearly states Macbook is at 30-35C when in sleep.
5. All temps I mentioned were measured with fan at about 1300RPM (system automatic).
Update (06/21/2018)
I have today applied Thermal Grizzly Kryonaut. Temperatures have gone down a little. Today at 31C ambient my MacBook idles at 48-49C and fan at 1300RPM.
I have run Cinebench CPU benchmark three times, one after another and temps stayed at 89-94C. On each run fans topped at:
1. 2300RPM,
2. 2800RPM,
3. 3400RPM.
GPU test pushes Intel GPU quickly to 100C. Fans spin up to about 3700RPM and temperature lowers somewhat. This test is short, however and fan would probably go higher with time.
I guess it is what it is, and there wasn't any issue to start with. I must have not realized that MacBook idles at about 50C in summer.
Is this a good question?
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1 Comment
When you boot the system after removing the logic board a process named coreduetd take up all processor capacity but disappears with a reboot. Then you have all spotlight indexing and so on at every startup..80C after boot or when processor is heavily engaged is normal..it you use graphics too it might go in the 90/100C area before fans start pushing. The temperatures you observed seem fine to me, nothing to worry about.
by arbaman