i7-9750h Core temperature large difference

Hi, I have some questions about the CPU temp, I recently got a Aero 15 OLED, but I found my laptop might have a problem with CPU temp, it's core temp is largely imbalance between 1st and last core.

This is idle with monitor app, some load on certain cores there are 10c temperature diff, that's fine and reasonable.



This is under full load:
Every core is 100% under load, but the 1st core just merely 67c, the last core reached 90c which cause early throttle on thermal. And the clock speed down to 3.5 Ghz. environment temp is 22c


Is this look like a hardware defect or TIM problem? Thanks!

 

The thermal paste might be unevenly spread out.

 

My unit also has same trend as yours (No.1 is cooler than No. 6) but under 100% load for all Cores, temperature difference is around 14 to 16 deg.C. I guess the uneven thermal paste spread is the culprit.

 

I don't see this with my 9750H

 

I had 2 15's oled and now the 17hdr. none of mine had this issue but I also repasted them myself right after purchase. My second 15 the screws were very loose and was not making good pressure with the cpu/gpu.

I would repaste it as its so easy on that system to do.

 

Thanks fo the info! I was planning to repaste based on all the comments above, But I have some some doubts about the display cable, how do you open it, it looks very fragile (M/B in the photo):

Thanks!

 

just pull it up and when putting back, it just snaps back on very easy no latch or tab to release.

Pull the rest of the cable back slow to keep the glue good so it sticks back down easily when done.

And please do not forget to unplug the battery it just slides straight out from connector.

 

Try looking at the screws applying pressure on the heatplate against the CPU. Tighten and loosen screws as needed to apply even pressure across the CPU. On models with odd numbered screws (3 instead of 4) it's been tough to get good even pressure against the CPU.

It can be due to uneven paste, but applied pressure evenly across the CPU should even out the paste underneath.

Try some pressure paper - remove the heatplate and clean off the paste on both the CPU and heatplate, apply the pressure paper and try to affix the heatplate with even pressure on the screws, then disassemble again to see how the pressure is being applied as visible in the pressure paper.

First, if you can figure out which screw is closest to the outer core which is getting too hot, try adding a 1/4 turn at a time tightening the screw - you may also need to loosen the opposing screw(s) to get slack to use to bring down and tighten the side that is getting too hot.

 

Thanks! everyone for help, I found the problem. I follow Darkhan's suggestion and took apart the heatsink, It's one of the worst I've seen:

The TIM on CPU is almost empty! and excessive TIM been pushed to board instead of core:



The TIM on GPU is even:



I collect those excessive paste and reapply it on GPU and CPU as well as heatsink:



Put everything back and fire up benchmark and burn-in app, never been better!

The laptop can pull 80w power constantly reach 4Ghz on 6 cores in Cinebench and adia burn-in, and all core stays with in 75c. It's a hefty 25c improvements.