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The following is strictly for informational purposes, as a few people have noted that their AK or GK units are running warm.

Not that I'm suggesting anyone else do the same, I'm attempting to improve on the CPU cooling of my GK1 board, as it is running warm as well. It tends to idle in the high 60s, and gets up into the 80s when under load. Again, I'm NOT suggesting that anyone else do this. I'm simply posting this in case people were wondering how they might do this, if they choose to. My GK1 and AK3 are both out of warranty, so I don't mind experimenting on the lesser used of the two. The worst that could happen is that it just doesn't help.

This board is actually now from my AK3 case. To explain, I have both a GK1 and an AK3. The GK1 is a Celeron J4105 with 4GB of RAM and 64GB storage. The AK3 is a Celeron J4125 with 8GB of RAM and 120GB storage. Because I like the case design of the GK1 more than the AK3, and because the board dimensions and layouts are identical, I swapped boards. I did this last year. So, this board, which is the J4015/4GB/64GB board, is one I just took out of the AK3 case. Additionally, you'll notice that this board does not have WiFi antennas connected. I completely removed them and disabled the onboard WiFi in the Device Manager. I instead use an inexpensive USB WiFi antenna. I do it this way because of the WiFi issue that some have experienced with the AK units when an HDD or SSD is installed under the lid. I experienced the same issue, so this was my resolution.

Board as it normally looks...

Board with heatsink/fan assembly removed...

Board with fan/heatsink assembly removed, and with aluminum shim removed from heatsink. The thermal compound is also cleaned from the CPU...

I ordered a set of copper shims from Amazon, as well as an inexpensive digital caliper, as I don't have one. I'm going to choose the proper copper shim, apply Arctic Silver 5 to the CPU, place the shim, then apply Arctic Silver 5 on top of the shim, then place the heatsink/fan assembly on top and reinsert the screws and springs that hold it down. Hopefully this will better transfer the heat from the CPU to the heatsink, resulting in a cooler CPU.

When I get the shims I'll finish this project, being sure to take pictures as I proceed. I'll post the pics, and the results, when I do.

Again, this is not a request for help, just an informational post.

Thanks, Gabe, for sharing.❤ I will put your post on top. We will better optimize the heat dissipation of the machine.

Part 2:

I received the shims and caliper today, so I decided to finish the project. The aluminum shim that was originally used, and which was stuck to the aluminum heatsink with some type of gray epoxy, measured 20mm x 20mm x 1.4mm. I used a 15mm x 15mm x 1.5mm copper shim, only because I couldn't easily find any 20mm x 20mm in size, and it was either 1.2mm or 1.5mm thickness. The CPU is much smaller than the shim, so the 15mm shim is fine. As well, because the heatsink is held down by the coil springs on the screws, there is some give, so a 1.5mm thickness was fine.

I cleaned the CPU, the shim and the bottom of the heatsink to ensure there was absolutely no dirt or oils. I washed my hands with some heavy soap so they were dry of oils too. I used a very small amount of Arctic Silver 5 on the CPU, then set the copper shim directly over it, making sure to get it centered as best I could by eye. I then put a small amount of Arctic Silver 5 on the top of the shim. You can see a little string of the compound from the blob to the edge of the shim in the picture, but being that this compound spreads out under pressure and heat, I saw no need to mess with trying to wipe it away, as that would have risked moving the shim out of place on the CPU.


I then carefully placed the heatsink directly over the shim, making sure to line the three screw holes up, and I lowered it evenly. Once it was in place, I put the springs and screws back in, one at a time, but didn't tighten them down all the way until I had all three in, and I did it a little at a time with each one until all three were tight. And because the heatsink is actually held down by coil springs around the screws, it's even better for the compound, as the pressure is even. I then carefully reassembled the unit, being sure to reattach all wires and reroute them where they are supposed to be.

The following snapshot was taken eight minutes after starting a stress test with Prime95. You can see in the task manager that the CPU is pegged to 100%, which is one of the things that a Prime95 stress test does. The memory isn't far behind. The temperatures is the small yellow number down in the taskbar (73).


The next snapshot is approximately 1.5 minutes after ending the Prime95 stress test (now 53 degrees).


A 20 degree drop in approximately 1.5 minutes.

The conclusion:

Replacing the aluminum shim and epoxy with a copper shim and a good thermal compound helped considerably. The temp still isn't as low as that of a desktop computer, but then a desktop computer has much better airflow and heat dissipation and costs three to five times as much, if not more. To have the temp be only 73 degrees after eight minutes of a Prime95 stress test is astonishing. Had I done the same with the original configuration, it wouldn't have surprised me if the CPU hit 90, and possibly even causing the max CPU temp protocol to kick in, automatically lowering the CPU performance so that the temp can come down.

Now again, the only reason I did any of this is because the PC is out of warranty, and I don't really use it for anything. At this point it's a backup to a backup to a backup, so I didn't mind fiddling with it. If something bad had happened to it, it wouldn't have been that big a deal.

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A few suggestions for ACEPC regarding the cooling design...

1. The heatsink should probably be a bit smaller. It's so large that it's having a hard time dissipating the heat.
2. Use a copper shim instead of aluminum to bridge the gap between the CPU and heatsink.
3. Use a good thermal compound rather than the epoxy that's used between the shim and the heatsink. There was some type of compound between the CPU and the shim, but there was epoxy gluing the shim to the heatsink, and in between them.
4. Set the cooling fan to come on at a lower temperature. Perhaps 60 degrees. Maybe this can be achieved with some type of BIOS or software tweak.

Thanks to Gabe for the tutorial. This is very helpful for improving heat dissipation. I have contacted the factory personnel. And will arrange follow-up rewards for you. You deserve to be rewarded.

Today I did the same with my GK1 with the J4125 based system board. Like the AK3 with the J4105 based board, it helped bring the temps down a bit and also helped in allowing the CPU to cool more quickly after an activity that raises its temperature.

Though I don't use either of these two units very much, and the AK3 with the J4105 even less than the other, it was installing Windows 11 in the GK1 that prompted me to finally do this.

hey Gabe, I probably missed it in your posts, but what do you use for CPU temperature? It looks pretty useful and I might want to run it on my own system to monitor things.

dragonpoo wrote: ↑Wed Dec 15, 2021 4:02 pm hey Gabe, I probably missed it in your posts, but what do you use for CPU temperature? It looks pretty useful and I might want to run it on my own system to monitor things.

I use Core Temp. I change of few of the settings from default in order to get it to always be showing in the taskbar, as well as the particular Windows taskbar setting (Select which icons appear in the taskbar).

Hey Gabe, thanks, I forgot about that software. I just downloaded it to my system and noticed the default Goodgame Empire install option, so if anyone else tries to install it, make sure you disable the adware link.
My system is simply running Windows 10 21H2 (no real software installed yet) and I typically RDP to it. Seems that 50-55 C is a regular thing for it, with a max of 69C right now, so I'm going to keep an eye on it. That feels a little warm for my expectations.

Good advice. I had forgotten about the add on things it tries to install.

The 50s isn't too bad, but yeah, it's higher than what one would expect from an idling PC. I sometimes find that after a few minutes the temp goes down a little. I think at startup some 'extra' Windows processes are running that eventually stop.