How to optimise a PC build for heat output

I live in Australia in a Room with poor ventilation. It’s currently 30°C (86°F), with peaks of 32°C (90°F) according to weather sites, but I have seen my room reach 36°C (97°F) with my computer on.

I think you will all agree that is an unbearable temperature. Or at least uncomfortable enough to be a problem worth fixing. I want to be able to code in the afternoon.

First of all I want to mention that AC is not a possibility, just because of where I live. I can’t change the house. But I do have some ways of improving ventilation and I’m going to try some of those.

Having said that I wonder if there is stuff that I can do to decrease the thermal output of my machine?

Here is what I’m working with (Both Ubuntu);

  • I have a laptop (Ryzen 7 5something) good enough to write code but makes my lap uncomfortably hot if it’s resting on it.
  • Desktop PC, with a Nvidia 1070, and a Ryzen 9 5950x.

My ideas In terms of free software changes:

  • Maybe I can change the power curves for both so they only use full power when they actually need it?
  • Maybe disable some of the CPU cores unless compiling?
  • Limit power for devices? Maybe it won’t actually impact speed as much as I think

Possible Hardware changes:

  • Orientate fans to cool PC better? Maybe that will increase efficiency?
  • Higher efficiency power supply would likely reduce heat output.
  • Maybe it’s worth buying an M1 device to write code on. I want to support macs eventually with the software I’m developing and the efficiency on those seem good.

Does anyone here have any thoughts/advice?

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bruh, buy an AC before you buy a new laptop because your rooms too hot

disable Precision boost overdrive and set windows to power save
Install MSI afterburner, set the power % to the lowest, and if possible, undervolt

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I can’t install an AC, so what’s the point and I’m going to buy an M1 or an M2 eventually anyway.

I could possibly get a portable AC but I doubt it would fit all that easily.

Mate your room sounds exactly like mine lol.
Try and get the best airflow u can through the room, position the exhausts closer to a window if possible. Grab a box fan and place it with the exhaust of that fan pointing out of your window. Heck stack 2 box fans at the window exhausting out if u can. Turn on a ceiling fan if u have one… in essence try and get your room working like your pc, pull in cool air from your door (or window) and out the opposite. Portable air con does work a bit u can put the exhaust at your window as well

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I believe fellow Aussie @gnif went to some interesting lengths to get cool and quiet.

Has water cooled the PC with the radiator external to the house… Like tubes come out of the PC, through the wall and into a car radiator outside to dissipate the heat.

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Reduce backlight/brightness on the monitor. If you can choose/change monitor get one with local dimming array or a mini led and use dark themes.

Undervolt/underclock, or turn-off the desktop, turn off any LED, (code on laptop + monitor only).

Fans can actually use a substantial amount of power and all they do is shift warm/cold air around and add noise - getting a lower CPU temp by increasing the fan speed won’t get the room temperatures down.


And as far as non-desktop stuff, go for the usual, open shutters and blinds after sunset/before sunrise and at night, close during the day - rotate open windows so that ones that are open are in the shade.

Fans shift air around, and mix humid and/or warm air with colder. If you can make drafts around the house. How windy is it outside typically?) those tend to be more effective than fans. (and you get more oxygen to breathe which will make you feel better and code smarter™)

If you have a humidity sensor, and it’s showing 60% or higher, that may be uncomfortable, 35-40% is still healthy, you may find yourself reaching for water more often. There’s no way to dehumidify air without adding more heat / using power and if it already feels too warm, a small indoor dehumidifier is not the way to go. If outdoor humidity is lower than indoor, even if it’s 33⁰C outdoor, ventilate.

And then, take cold/luke warm showers to destress, go for afternoon relaxing walks bring an audiobook, rearrange meetings to make it happen and feel better - I have no idea what else you could do.


m1 are crazy efficient, my mom got a new MacBook Air and I was remoted into her machine while using her webcam and microphone to talk to her and was installing things and setting things up and at one point near the end of all that, the soc temp was 27⁰C and her room was 20⁰C. The MacBook Air is fanless (ironically :slight_smile: ).

If you can work off of a 16" MacBook Pro (no external monitors or keyboards), that’d be awesome.

I’m not sure what kind of development you do, but obviously if you can rent hosts or remote into hosts to do building and testing remotely, instead of locally, that could be a useful option sometimes, vscode is great for this type of thing.

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You kind of have to do something like that if you don’t want to heat up the room you’re in at all.

If you can’t cool the room, then maybe duct the airflow into existing HVAC ductwork. Whether or not that’s more or less work than full on watercooling is hard to say.

I have three monitors, I might look at their heat output.

I didn’t think about humidity and I might try to fix that.

I wonder if the best solution is to just change my routine so that I’m not in my room at this time at all.

To be clear, does your room have windows in it?

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Like you surmised, work at night or early morning.

I am in the same situation. I should note I have always prioritized my PC’s speed at the expense of heat. I personally just live with the heat… when it gets hot, I sweat a lot, but air conditioning is pretty much out of reach for me.

I have NEVER had a house with air conditioning in it, and i’ve always been able to run my PC at full speed, even on very hot days. How did I do this? A variety of ways, but most of them revolve around getting better airflow to my PC.

My most recent PC, I have built specifically to address this problem. And I do it with air cooling (no water cooling).

In my region Last summer we had a couple weeks where the temperature got up above 100f in the shade (37.7c). Yet my computer still chugged along with nary a slowdown.

This is my current build with a 5950x and a 3090.

Click the blue down arrow to expand this post and see pictures of what I built with the exact hardware included…

If you can not afford to build a new machine, here is a very simple solution. If you are using a tower PC, take the side panel off your computer. And get a standard box fan - and plunk it down blowing directly into your pc.

(not a joke picture you can easily do something like this and it works fine)


If you want a quieter fan, get a full size box fan meant to cool a room, and aim that directly into your pc at a slow speed. That will work fine too but it has to be right next to the open computer.

A good solution for this problem is with your next builds for your PC - get a good HIGH AIRFLOW case. Watch Gamers Nexus https://www.youtube.com/c/GamersNexus/videos and do a search on his channel for the best cases. You want something where the entire front is basically open with some sort of mesh covering and big fans.

Here is a video of his where he covers the type of case I am talking about.

The Fractal Meshify cases are decent too.

I also just realized that you want a slower computer so that it runs cooler… ummm.
Get a box fan and leave the door to the room open, if you have a window, open that too…

One way to ‘beat the heat’ on a personal level is to get a t-shirt, soak it in the shower, wring it out a bit, then put it on.

Again, not joking - wear wet t-shirts. This method will keep you cool for about 30-40 minutes until the water evaporates out of the shirt. When it does and you get hot again, then get your t-shirt wet again. Repeat this throughout the day as needed to stay cool. You can also aim a fan at you (but this will dry your t-shirt out faster) to cool yourself better.

That is what I had to do during a few days last summer when the ambient temperature got up to 110f (43.3c) for a few days in my region.

The ONLY solution for a PC with lower heat output, without replacing the hardware, is to replace the hardware… buy lower power PC’s. Anytime a computer is using more power, that power usage will turn into heat eventually. This means trying to find highly power efficient PC parts. These will inevitably be parts that are typically not as powerful but instead focus on power efficiency.

You can try under-clocking your pc too, but i’ve never really experimented with that.

Honestly it sounds like you really need to look into home cooling methods.

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If you have a window, you could look into portable AC units. These sit on the floor and have a tube or two that run to the window. Even if you are renting your room and can not change the house itself, a portable air conditioner could be a solution. Look for one that is “Self-Evaporating”.

Conventional portable AC units work by cooling the air in your home, and a small amount of moisture is removed from the air in the process. This moisture needs to be removed from the machine periodically, and this means emptying the drainage tray regularly. Self-evaporating portable air conditioners offer a solution to this and remove the need to empty the machine. Other than moisture collection, they work in exactly the same way as a standard AC, with air being drawn into the machine using fans, cooled with condenser coils, and blown back into the room.

The moisture is gathered in the same way, but then half of it is used to cool the internal mechanism of the AC and keep it working correctly. The other half is re-evaporated within the machine and dispersed back into the air. This moisture is then used to help cool the air in your room and circulated back into your home.

This operation means that there’s no drainage tray to be emptied, and you can have peace of mind that no excess moisture will linger in the machine and cause internal damage. This style of portable AC works well in areas where you need to use it constantly, but you don’t want to do constant maintenance on the machine. Self-evaporating units also work well in dry rooms or homes where you don’t want to lose too much moisture from the air.

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You could downgrade the 5950X to a 5700G, that would cut a lot of heat from the system.

Other than that, I would start looking for a case with a radiator that flows straight through the case, and watercool that.

When I first saw the thread title I was thinking you were in a cold country and wanted to use the computer to help heat your room…

I’m from a cold country.

If heat is such a concern, then you really have no other choice but to build around more efficient and cooler running hardware. Still, there are a few things you can do to mitigate the problem.

  • Box fan near a window. Set is so it exhausts towards the open window.
  • Placing your desktop PCs near a window.

It has 1, but the airflow is basically non existent unless I keep my door open so uh.

I keep my door open.

I wish that was my issue lol. I could contribute to science with folding at home and heat my room.

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1 window will work with the portable self-evaporating air conditioner I mentioned.
And if you don’t own your house, and the owner is preventing you from owning an air conditioner. There is one other solution I use.

This solution I use personally, and I can say it works! It will lower the temperature in your room quite a bit, you should be surprised by the results.
I made this handy image to help show what I mean more clearly.

This plan only needs tape and cardboard. I’m guessing you at least have access to those.

Now this gets a bit complex to describe, so stay with me here…

Imagine air like water, and your fan like a pump pulling through a single opening from a very large pool. The idea is, you want the fan to pull in cooler air from outside, while expelling warm air back out into the world outside.

But you only have one opening, so you can’t easily divide the flow with just a fan, unless you force the air to actually exit the room entirely before it gets sucked back into the fan. This gives some of the hot air from the room time to escape into the world outside, (although some of it will get pulled back in, it won’t be as much if you can force the air out the window first)

Use some cardboard taped to the fan and maybe along the edges of the window too. Seal the fan as best as possible to the window and leave a good sized gap open on one side.

This will force the fan to pull air in from the outside instead of just blowing it around the room. The taped cardboard seal will prevent the fan from picking up any air from inside the room, and the open space that you leave in the window will force the hot air to leave the room and go into the great outdoors before anything can be pulled back in through the fan.

This will give the heat coming off your PC a chance to stay outside. Some will naturally get pulled back in by the fan, this can’t be helped. But the forced airflow path will push a great deal of heat out through the window.

Of course put cardboard to seal the top and bottom of the fan to the window as well.

The key is sealing the fan to the window as much as possible so the fan has no choice but to pull air in from outside first.

…did I really spend half an hour on a silly MSPaint drawing? … did I put an angry face on the computer in the image?.. yep… yep… I did that…

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I live in the Philippines and I understand hot climate as well. You didnt seem to specify if you own the building you are in, just in case you do:

  • Paint the roof white.
  • Have lots of plants - trees do wonders for shade and reduces your house/building exposure to direct sunlight. Have them along the west and east end of your house.
  • If digging is an option or if you have a basement/cellar, put your stuff there. If your mobo has a thunderbolt internal port, maybe you can use HDMI to passthrough monitors and keyboard upstairs where it is warmer.
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