exotic cooling Additional cooling for compact PC

[OutsideTheBox]

First off I have no clue where to post this. Here, in build plan, or in hobby electronics ... or somewhere else complete ... but for me it is most likely to be posted here.

I have a Zotac ZBOX-EN1070-BE* which I upgraded from a Core i5 6400T to a i7 7700T with same tdp ... already a while ago. Runs fine so far. But as soon as I fire up something demanding I recognized that the PC didn't was as fast as it should. After finally getting around installing MSI afterburner to monitor the system constantly I found out that above 75°C the PC throttles ... which made me adjust the fan curves so that the fans run at max speed at 70°C already. Alas ... no luck the heat sink is way too wimpy. it reaches 75°C after a few seconds and stays there (and throttles ... and it seems a lot)

And I can't replace it either since it once unit with the graphics cooler and the VRM cooler.

 

So I got the wild idea in my head to stick additional cooling on top of existing one. Basically cooling the heatsink that is then cooling the CPU (and partially the GPU as well). see:

Spoiler

Which would require me to saw a hole in the case for the "conventional" cooler to go through. But I don't know if that has too much effect ... so my wild idea is to place a peltier element (106W) in between that and the coolers and control it with a raspberry pie 0 and ready made set of temperature probes (so that it doesn't cool below ambient)

 

What do you think ... would it work without peltier and is that with it just overkill? Any other ideas?

 

___________________________________

*= Pretty much this box ... for reference ... they don't advertise my model anymore ... but this one is basically the same (only updated processor) https://www.zotac.com/product/mini_pcs/magnus-en1070k

Part list:

1. Computer (see above)
2. Peltier element https://www.conrad.de/de/p/tru-components-hp-127120-peltier-element-14-5-v-dc-12-a-106-w-l-x-b-x-h-40-x-44-x-2-8-mm-1572742.html
3. Pi zero https://www.conrad.de/de/p/raspberry-pi-zero-512-mb-ohne-betriebssystem-1693283.html
4. Relays https://www.amazon.de/dp/B07CNR7K9B
5. Sensor https://www.amazon.de/dp/B00D2UFKK0 or https://www.amazon.de/dp/B01MZG48OE 
6. Power supply https://www.conrad.de/de/p/mean-well-lrs-150-12-ac-dc-netzteilbaustein-geschlossen-12-5-a-150-w-12-v-dc-1439463.html
7. CPU cooler: ... I think any would do ... but maybe this one https://www.amazon.de/dp/B01KVNCEIG/

 

[jaslion]

I get where you are coming from but have you tried running it without the top case on to see if it isn't simply an airflow issue before doing all of this? This will also kinda ruin the whole purpose of this system which is being nice and compact.

[Fasauceome]

17 minutes ago, OutsideTheBox said:

I upgraded from a Core i5 6400T to a i7 7700T with same tdp

Unfortunately the TDP is not the same, despite what Intel says. A quad core vs a quad core with HT that are only one generation apart really can't have the same TDP if one has more performance. It's possible you're facing a power delivery issue, you should try disabling hyperthreading using Intel XTU to see if your CPU clocks get higher.

[NunoLava1998]

PCPartPicker Part List

Case Fan: Delta Electronics - AFB1212GHE-CF00 240.96 CFM 120 mm Fan  ($30.98 @ Newegg) 
Fan Controller: Lamptron - CW611-B Fan Controller  ($71.48 @ Newegg) 
Total: $102.46
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2019-05-09 10:32 EDT-0400

Draws 35W ((and makes you deaf "67dB"))

[OutsideTheBox]

1 hour ago, NunoLava1998 said:

PCPartPicker Part List

Case Fan: Delta Electronics - AFB1212GHE-CF00 240.96 CFM 120 mm Fan  ($30.98 @ Newegg) 
Fan Controller: Lamptron - CW611-B Fan Controller  ($71.48 @ Newegg) 
Total: $102.46
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2019-05-09 10:32 EDT-0400

Draws 35W ((and makes you deaf "67dB"))

The sad problem is ... the only place where I could stick this fan is ... up my bum. There is no place in this case where I could put it.

To describe how little space there is left in this case ... I had to go with low profile heat sinks for the NVMe SSD and even that is scraping against the case ... (underside where there is more room ... I think).

 

I have a cooling pad for laptops with a huge fan and massive airflow (I think) under it already (cools my SSDs).

I left that open and replaced it with a wooden frame (on which the computer can rest on ... otherwise it would lie on the NVMe SSD)

TBH here I also thought about cutting a hole over the CPU intake, and put an additional fan that that pumps more air in, but that also might screw the airflow inside the case ... I think it's meant to go over some places from the outside in.

 

1 hour ago, jaslion said:

I get where you are coming from but have you tried running it without the top case on to see if it isn't simply an airflow issue before doing all of this? This will also kinda ruin the whole purpose of this system which is being nice and compact.

Unfortunately not an option. It's what holds the motherboard in place. also has attached  the antennas to it. I could try to run the board bare ... I think ... but there was a reason why I decided to try against that

 

1 hour ago, fasauceome said:

Unfortunately the TDP is not the same, despite what Intel says. A quad core vs a quad core with HT that are only one generation apart really can't have the same TDP if one has more performance. It's possible you're facing a power delivery issue, you should try disabling hyperthreading using Intel XTU to see if your CPU clocks get higher.

They lied to us. ... I might try that first before trying destructive measure ... since case parts can't be replaced (not sold) .... I tried to get some but no luck anywhere. The only way to get case parts is to buy a new machine.

Anyways I'll see when I come around to do that ... (cause I rarely rebooting the computer ... once 1/4 year or less)

But I still think that's a thermal issue. Since the CPU clocks high (~3700Mhz), then gets warm (~78°C) and drops ~3400Mhz

Oh ... I checked the program I use also has check for power limit ... and yes it has power limit spikes.

[Fasauceome]

12 minutes ago, OutsideTheBox said:

But I still think that's a thermal issue. Since the CPU clocks high (~3700Mhz), then gets warm (~78°C) and drops ~3400Mhz

3.4 GHz is still faster than the turbo speed of the 6400t, you shouldn't feel sluggishness from that. When you say "the PC doesn't feel as fast as it should" what is the specific deficit?

[jaslion]

Did some googling:

 

6400t seems to consume around 30-35w of power.

The 7700t hovers between 50-65w of powerdraw.

Combine that with a 1070 on a 180w powerbrick and you may have some issues there.

 

This machine was purpose built to only handle the specs it came with max. An i7 7700t generates a lot more heat as shown by the higher average powerdraw. I'd just leave it running at 3400mhz on default fan speed as it will still be better than the 6400t it came with.

 

I'm actually kinda surprised it works fine with a 7700t + 1070 on a 180w powerbrick.