Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

1096bimu

macrumors 6502
Nov 7, 2017
437
539
It will have practically zero impact on temperatures, you have a very poor understanding of how cooling works.
fans don't do any good when you have no surface area.
DSC00849.jpg DSC00850.jpg

This is how you can actually boost cooling performance. I can cool my MacBook at max power even with the internal fans at idle. It's not even radical, it still works like a normal laptop.
 
Last edited:
  • Like
Reactions: Ploki

Ploki

macrumors 601
Original poster
Jan 21, 2008
4,322
1,560
wait am i getting this right? You used thermal tape all over heatsinks, then just flipped the laptop and (presumably) thermal-taped a huge-ass heat sink on it?

Have any before/after benchmarks?

hm, technically i could use a smaller heat sink with active ventilation if i had a hole in the bottom and sticked it directly to the heat sinks.
(wonder how much loss you get by double-taping and having aluminium in between)

Do any "non-stick" thermal conductors exist? I dont want any glue residue on my heatsinks.

This could make the i9 scream...
 

maflynn

macrumors Haswell
May 3, 2009
73,682
43,721
cutting a hole under CPU/GPU heatsink and install a huge sucking fan
The internals are designed for a certain airflow and cutting holes may impact that. With that said, I believe someone did that in this forum and had some positive results.
 

Queen6

macrumors G4
You would need push a significant volume of air through the heatsync's for any effect, especially with the i9 as the TDP is so high. Bottom line is the cooling system is inadequate versus the thermal output of the processors. You could try to use the base plate to dissipate some heat, equally cooling a 28W CPU versus the I9 with over 100W...

Q-6
 

1096bimu

macrumors 6502
Nov 7, 2017
437
539
wait am i getting this right? You used thermal tape all over heatsinks, then just flipped the laptop and (presumably) thermal-taped a huge-ass heat sink on it?

Have any before/after benchmarks?

hm, technically i could use a smaller heat sink with active ventilation if i had a hole in the bottom and sticked it directly to the heat sinks.
(wonder how much loss you get by double-taping and having aluminium in between)

Do any "non-stick" thermal conductors exist? I dont want any glue residue on my heatsinks.

This could make the i9 scream...
No, I thermal coupled the heat pipe and the bottom panel with thermal pads. I can then just place a big heat sink on the bottom panel to cool it.
With the mod alone, no extra heat sinks, when placed upside-down I get 20 degrees cooler while running games, down from almost 100 to 77 degrees.

With the large heat sink and an external fan, the internal fans will stay at minimum speed with temps yet a few degrees lower at around 73.

It won’t make the i9 scream because peak turbo speeds are still limited by thermal paste performance. With this setup I have here I still hit 100 when running over 4Ghz even with a bock of ice cooling the bottom panel. This indicate a thermal bottleneck with the thermal compound. You would need to change that into liquid metal for a significant boost in peak performance.
Benchmark scores are not significantly changed, they just don’t drop at all over multiple cinebench runs. The first run is only like 20 points higher.

It would be possible to just stick this sink directly on the heat pipe. I’m guessing you’ll get minimal improvements because the thermal resistance of the back panel is minimal over such a large surface area. Applying liquid metal would make a much bigger difference when combined with my thermal mod.

Obviously you could go totally nuts, you can put a water block on the thermal system after applying liquid metal, but I don’t see the point because you can get a desktop computer with all 6 cores running at 5Ghz for half the cost.
 
Last edited:
  • Like
Reactions: Ploki

maflynn

macrumors Haswell
May 3, 2009
73,682
43,721
Here's the thread where a member drilled holes. I think your plan may be a bit more ambitious but he saved himself 5 to 6c on idle. Its an old thread and he did it on an old laptop

Now my MBP is running 5 or 6 degrees celcius coller in idle than before.
 
  • Like
Reactions: Ploki

Ploki

macrumors 601
Original poster
Jan 21, 2008
4,322
1,560
No, I thermal coupled the heat pipe and the bottom panel with thermal pads. I can then just place a big heat sink on the bottom panel to cool it.
Really? And it works SO well?
Dang, I could just cut a hole in the desk and replace it with a giant heatsink in that case. I might as well do that. Thanks for your input
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.