What are the best substitutes for thermal paste?
Updated: January 30, 2023 1:28 p.m.
Maybe you were looking forward to upgrading your CPU cooler, but were disappointed when you realized you had to glue the CPU IHS back on.
Maybe you’re in need and need to use your overheated computer, but you don’t have thermal paste on hand.
Or, maybe you’re just interested in some PC building shenanigans.
Anyway, on this page you’ll find a few substances that can technically be used as a temporary alternative to thermal paste, although I can’t recommend it.
What makes a good thermal paste substitute?
Thermal paste, a gray thermally conductive liquid, sits between the surfaces of a microprocessor’s IHS (integrated heat sink) and the cooler heat sink.
You see, the heatsink and the IHS are not absolutely perfect machines; they have tiny cracks on their surfaces.
When the two surfaces are pressed together when mounting the cooler, tiny air pockets form inside these cracks. Air is a poor insulator of heat, so air pockets end up slowing down heat transfer considerably.
Thermal paste fills these cracks and gaps so that heat can move more efficiently from the IHS to the heatsink.
Any alternative to thermal paste should do the same. It would need similar properties to thermal paste (consistency, thermal conductivity, etc.) to facilitate heat transfer in the same way.
Best Thermal Paste Alternatives
These alternatives aren’t as effective as thermal paste, but you can use them in a pinch to prevent your CPU from overheating.
Innovative cooling graphite thermal pad
Advertised thermal conductivity
If you don’t have thermal paste, thermal pads are the next best thing. If you must use a substitute, I recommend using a thermal pad, as it is designed to transfer heat between components.
Pads are much like thermal paste, but less effective, as their solid nature prevents them from filling in air bubbles in the same way as thermal paste.
Yet unlike many other liquid substitutes you’ll hear about online and on social media, a thermal pad won’t melt or damage your CPU or motherboard.
They also have great longevity. If you have a low power microprocessor that doesn’t need the most efficient cooling to maintain normal temperatures, you could probably get away with using a thermal pad instead of paste.
Next, we have toothpaste. At first glance, it seems that toothpaste could potentially share some properties with thermal paste. And it does – the two liquids don’t differ too much in consistency.
Thermal paste is of course more conductive. But the toothpaste will prevent your CPU from overheating and shutting down automatically, which means you can use it in a snap.
The problem here is that toothpastes vary wildly from brand to brand and tube to tube. The results you get will depend on your particular toothpaste.
There is also the fact that toothpaste contains fluoride, which is a corrosive element. Although fluoride is not concentrated enough to cause noticeable damage to the IHS or heatsink, it can leave traces.
If you use toothpaste, don’t expect it to last very long. It can last from a few minutes to a few days before completely drying up, but not more.
Aluminum powder mixed with petroleum jelly
Aluminum powder has excellent thermal conductivity, and petroleum jelly (or petroleum jelly) does not dry out quickly from heat. Carefully combine the two and you have a goo that you can use as a temporary substitute for thermal paste.
You will need to mix the aluminum powder and petroleum jelly for about 10 minutes to get a workable mixture.