Yes, that's right. A laptop power supply.

This afternoon I was playing Minecraft on my ASUS laptop. As many Minecraft players know the game is written in Java which, on high settings, can force quite a high demand on the computers CPU. After two hours of playing my laptop popped up a notification of "[switched to] Battery Mode". Check that power supply is still in laptop, still in wall, however no green "power" LED on the power transformer. Pick up the transformer and it is insanely hot to the touch, causing the floor to be very warm underneath it. I guess there's some sort of temperature cut-out on the supply to stop it catching fire but what does one do with a flaming-hot power transformer? This has never happened to me before (unsurprisingly) and since unplugging it from the wall and laptop I have just left it to cool. I've not used it since so has it been fried? The laptop itself is running fine (using it now). I was thinking about replacing the supply anyway but is there a "best" way of cooling one down, just in case?

Granted it's probably not going to happen to many people (and now I will know to play with more breaks, and probably on my desktop instead) but still...for science?

  • Get a plastic or metal bowl (maybe one from the kitchen?) that has a reasonably flat bottom, fill it with some water and put it on the top of your adapter. Glass ones or think plastic ones will not work because they conduct heat poorly. You can also get a large piece of metal foil and put it under the adapter to help both sides cool. Warning: Don't fill too much water as the bowl may topple over.
    – billc.cn
    Aug 1 '11 at 17:30
  • 3
    I would simply put a pen under each end of the PSU. Just getting it up off the floor should help immensely.
    – EBGreen
    Aug 1 '11 at 17:32
  • My Dell power supply does this all the time on my alienware. I have the m11x so I can fit it on my cooling mat next to my laptop. My suggestion would be to get a laptop cooler that is larger than your laptop and then lay the adapter next to your laptop.... This might also depend on the size of your cord from adapter to the wall, I know dell sells them up to 12 feet which is nice or this purpose. Aug 1 '11 at 18:09
  • 7
    A bowl of water on or near a PSU is a disaster waiting to happen (IMHO)
    – Linker3000
    Aug 1 '11 at 18:45
  • 1
    This is an old post, and many people have suggested ways to do what was asked. Realize, though, that what is getting hot has a lot of insulating material between it and the outside--a plastic shell, captive air, the parts may be potted in plastic, etc. If components are actually overheating, anything you do cooling the outside will be too little, too late to have a real effect on the components that are overheating. So it doesn't really help, and could mask an actual problem, or even create a hazard.
    – fixer1234
    Nov 6 '16 at 3:37

Absolutely, the best thing you can do is to allow the PSU to cool naturally, don't try to cool it quicker as doing so may cause damage (if it's not already damaged). Allow it to cool fully before attempting to use it again, and monitor your laptop and the supply when first using it in case it has been damaged.

  • Just curious, as I have never heard that rapid cooling can damage equipment (other than sticking in in liquid nitrogen or something where it gets very brittle) can damage anything, can you source that?
    – soandos
    Aug 1 '11 at 17:31
  • 3
    My source is experience mainly, though in terms of electronic equipment Differential Cooling would be the main problem with any rapid cooling technique, which may lead to cracked solder joints and burst electrolytic capacitors amongst other things (though in this case, burst caps are likely anyway). Natural cooling of a modern power brick should reduce - though not eliminate - the chances of problems caused by Differential Cooling.
    – Mike Insch
    Aug 1 '11 at 17:36
  • Why doesn't power adaptors have any sort of ventilation to cool down??? Literally a completely sealed black box. That means eventually, it will overheat. Can't be good design.
    – NoName
    Dec 8 '19 at 21:35

Raise it off the floor as suggested and train a desk fan on it - and/or get a higher wattage unit.


This is a fairly old question but I have a rather unique solution. Buy a good laptop fan just for the power brick, it won't provide so much cooling that it will cause damage but will keep it running at a reasonable temprature. I own both an ASUS ROG gaming laptop and an Alienware one as well. Both power supplies have heat issues.

Personaly I use a box fan leaning at an angle against the wall and I have made a support to hold the psu against the fan. This keeps it very cool.

The picture I attached is an older setup in which I used the power cables size to hold it on the fan! (also the psu has feet which fit in the fan notches

My Fan Setup


I came up with a way to keep my power supply cool.

I have an m17xr3 Alienware laptop which power supply gets extremely hot, especially with overclocking. It's just drawing more power from the supply than it used to. Now that I have unlocked the BIOS and am pushing the CPU and GPU harder, which in turn draws more power the CPU, has gone from stock 2.4GHz up to 3.7GHz, which it seems to have no problems.

Doing very stable temperatures, no real increase from stock, I did adjust fan timing so they come on earlier now, but overall temperature never exceeds 80 degrees Celsius. The main issue was the power supply getting so hot you couldn't touch it.

I solved this by cutting a rectangular whole in the top of the plastic on my PSU and attaching 2 old CPU heat sinks with the fans still attached to the metal plate. Inside the PSU, some heatsink paste and an old 12V power adapter to power the fans.

It never gets above 20 degrees Celsius now.

Here is a pic:

power supply cooler


If it is hot to the touch, but not hot enough to burn you (meaning, you can hold it uncomfortably), it's probably fine. Keep in mind that temperatures like 100 degrees F are considered relatively cool for electronic components. However, if it's scalding hot so that you can't touch it, it's likely that it shorted out and it needs to be REPLACED IMMEDIATELY OR FIRE!!! Less resistance, more inductance, more heat, or something along those lines...


A very similar solution like 'Elapsed's.

PowerTRC LED Programmable Message Fan W/custom Drawing - USB Powered (Blue Led)

I remembered that i got one similar to the picture, once i read Elapsed answer. Thanks!

Also you can look at different types if you want more cooling performance: https://www.amazon.com/gp/aw/s/ref=is_s?k=usb+fan!

P.S: To increase cool down, try LSerni's method below in comment section. Disregard this: I didn't tried but to increase cooldown you can wrap power adapter with aluminium foil (tinfoil). I think you should wrap it firmly by using Thermal paste. This way almost every surface of foil should be in contact with PSU. And that way notebook adapter can transfer its heat to aluminium.

CAUTION: If wrapping isn't firm; you cause your power supply unit to overheat because of blocked air current and very hot air pockets between tinfoil and adapter surface. So you need to try out a small piece of aluminium foil by applying it on adapter with the paste. if thermal paste made for CPU's will glue the tinfoil to the PSU's surface and keep it glued for a very long time, there will be no problem.

Complete the wrapping without cutting tinfoil. There should be an extra tinfoil as long as your fan's diameter. Direct your fan to this extra tinfoil and this SHOULD happen: PSU will transfer heat to tinfoil. Fan's air curent will cool down PSU faster because more air current will be in touch with more heated surface.

I know lots of 'if's, but maybe someone out there has both time and curiosity.

  • Wrapping the PSU in thermal paste plus aluminum foil is going to cool it down less, not more. If you really want to get creative, cut out two square holes at opposite ends of PSU plastic (voids warranty) and use its 19V output to drive two 6-cm 12V fans in series circuit, one blowing air in, one sucking air out. They'll draw around 1.5 - 2W and cool the PSU all right. The problem being that if the PSU overheats, then it is underdimensioned (e.g. a 65W with a laptop occasionally drawing 70-75W) and should be immediately replaced with a more powerful one. The overheating is a symptom.
    – LSerni
    Jul 16 '17 at 20:48
  • Thank you Lserni. I guess thermal paste only works between metallic surfaces or between certain alloys.
    – Kerem
    Aug 9 '17 at 23:13

Not kidding at all, I put an ice cold water bottle on top of it, cools it down and never over heats and water doesn't drip down too much and damage it. Not sure if it's fluke or not, but I have also noticed that the colder the converter the cooler my laptop is.

  • 1
    Depending on situation, this suggestion can be outright dangerous. If the bottle is cold enough and the weather humid enough that moisture condenses on the bottle (even with the warm air coming from below), it will drip on the power brick and, if it has a venting grill or is otherwise not sprinkle-proof, it might even short out.
    – LSerni
    Jul 16 '17 at 20:41
  • Hense why I stated, "water doesn't drip down too much and damage it" obviously, you don't have to be a genius to figure that one out. You'll find the power supplies are water resistant enough. Anyway, fair enough. Sep 9 '17 at 9:45

drill holes.. then attach a tiny fan on it.

Another option is to transfer the innards into another case that allows better natural ventilation. A 3d printed case with grilles might do

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