Does the Pentium MMX 200Mhz processor need thermal paste?

I replaced the fan on it and it has a small heatsink with no thermal paste on it, and I was wondering since the screen fizzes out if I leave it on the BIOS for a while (seems like it overheats). In DOS it works though, and haven't tried Windows.

  • 3
    It can't hurt...Of course it sounds like a larger problem, since that processor, has no thermal controls it wouldn't shut down even if it was overheating.
    – Ramhound
    Jul 30, 2015 at 16:24
  • From what I understand with this part, an HSF assembly is certainly required and was supplied with the processor as sold in retail packages. It would certainly be a good idea to use thermal paste.
    – bwDraco
    Jul 30, 2015 at 17:45
  • You really tried it with DOS? That said, DOS is pretty friendly on the CPU, since the vast majority of the time it's just waiting (and I'm pretty sure it doesn't busy-wait).
    – user
    Jul 31, 2015 at 8:36

3 Answers 3


If there is a heatsink, you really should apply thermal paste between the CPU and the heatsink to ensure proper flow of heat. As they say, better safe than sorry.


Every single pentium 1 I have worked on, from 75MHz up to 200MHz, had a heatsink and a fan attached (or a peltier element). So lets assume they need at least a heatsink

Next: Whenever you use a heatsink you also use either:

  1. A thermal pad.
  2. A thin layer* of thermal paste.

The reason behind this is that a heatsink might look nice, flat and polished to the naked eye, but in practice the surfaces of the CPU and the heatsink are not a perfect match. There will be many small air pockets. These hinder the transfer of heat from the CPU to the heatsink. Thermal paste can be used to fill these holes. Therefor thermal paste is almost always used.

In cases where the heatsink itself is not enough and even a fan is added, you certainly want to use thermal paste.

So yes, do use thermal paste.

*: Thin because metal conducts heat better than the paste. So you want to use as little paste as possible, but enough to fill al the holes.

  • ...but: does it need thermal paste?
    – Arjan
    Jul 30, 2015 at 17:45
  • I think that was the question the OP was asking :-)
    – Arjan
    Jul 31, 2015 at 7:23
  • Good catch. Rewrote answer.
    – Hennes
    Jul 31, 2015 at 7:37

Everything in me says yes to this. (Thermal paste helps make a solid connection between the chip and the heat sink.) I did have a Pentium Pro I kept as a paper weight, it still had some paste on it even after repeat cleaning attempts so I can for a fact state that processor used it.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.