please make a closeup photo of the plastic side of the cpu (the side that is now facing down on your picture.

I don't have this computer with me right now. But the back of the CPU looks like this:
http://www.cpucollection.ca/PIII500512100.jpg

Yes, indeed.. a pain in the a...

When you look inside one of the four holes you will see a small black pin whit what I call a "finger". You have to press that finger whit a small tong till it plops backwards.

You can replace the cooler whit some other kind, whit better removal possibilities. If one of the 4 pins are broken you have to.

I alteady tried to push those 'fingers' through the holes. But there was no movement. I was reluctant to push harder, afraid of damaging something. If you are sure that this is the right method, then I will apply more force tomorrow.

Those four holes go straight through the whole PCB. If you push straight, you shouldn't damage anything. I had to PRY my Pentium II apart to get at the space between the heatsink and the CPU in order to change out the thermal paste. I did lasting damage to the outer plastic cover, but not the PCB or the heatsink itself. If you're very careful, you can get it off. Don't worry about the pins or the heatsink, or even the black plastic cover on the back. The ONLY thing you have to worry about is the PCB inside with the CPU on it.

Good Luck those clips will break every time, you really have to pull extremely hard on those clips to get them off, not fun, not fun at all 😢

Inspired by this thread I had another go at removing the broken HS from my 650 MHz PIII, and finally got it off. However

1) It took a lot of force: both pushing the pins from below with a screwdriver and pulling them from above with pliers

2) Two of the pins broke during removal

Conclusion: Only do this if you intend to throw away the original HS

I picked up an original Cooler Master heatsink/fan for a Pentium III on E-bay and it works very well. It comes with a thermal pad already installed on it. If it had been thermal paste, I'd have cleaned it off with alcohol and used new paste, but I think I like the pad better. It'll keep the exposed CPU die from cracking under load. The heatsink also came with spring-loaded clips that can be easily removed at a later time, so that's a nice feature.

I have around 20 slot1 cpu's and it is simply amazing how allmost every single one has a slightly different cooling system. Some cpu's that barely get warm have HUGE heatsinks, others are fast p3's with very small heatsinks and a whining fan. Some have the pins, others have the much simpeler clip that you slide in place and keeps 4 pins from getting out.

Some p2's just have 4 holes with threat in them so heatsinks are screwed on with a bit of paste in between.

486 was the easiest, along with the first pentiums. Simple clip with little pressure, it didn't need a lot of flow. Great stuff, 2 second removal or fix.

slot1 could be a pain, and faster socket 7 needed better coolers and could break the socket clip. This happened far more often with socket A and s370: still not a good solution.

With p4 things looked better but the standard Intel cooler was a flimsy pain in the..... how hard can it be to design a good cooler? Well, for Intel pretty hard as the Core series got the stupid pins which can easily be damaged or not ''clamp'' hard enough.

At least there are the right holes to mount a good aftermarket cooler. Amd does it right the last couple generations.

Oem's can make some good mounting solutions as i have seen many systems from Compaq/Dell etc. that had their own creations that were much better than Intel's.

Eendje wrote:

I alteady tried to push those 'fingers' through the holes. But there was no movement. I was reluctant to push harder, afraid of damaging something. If you are sure that this is the right method, then I will apply more force tomorrow.

You do need to apply a significant amount of force to push the pins through the holes.

What I'd used to do was to sit a standard 6-32# case screw in the mounting hole against the pin, and then push down on the heatsink with the processor against a hard surface (such as a table). You'll hear a loud 'click' when the pin pops out.

It takes a significant amount of force (hence why you should push the processor against a table, instead of trying to hold onto the processor while pushing the pin through), but if you push down evenly on both sides of the heatsink you can avoid warping the processor PCB. The best part about this is it doesn't damage the clips -- you can re-use them if you need to.

I had to use my full body weight but it worked! Thank you all for your advice.

I have to say, gonianbl00d, although your method is very violent IMO, I can also attest to it working!

You see, I needed to remove this heatsink:

from my Pentium III 600E CPU, and, as you can see, your method was successful! (Do not mind the clip on the left; I broke that little piece on the end of one of its "legs" beforehand while trying to push on it with a crappy, skinny paintbrush, which also resulted in the paintbrush snapping; it was a dumb idea 😀; the "broken" clip still works, though, albeit at the cost of making it harder to remove).

I removed the plastic clips with two Philips screwdrivers. You need to put the heat sink on a table, pin holes facing up. You can loosen the clips by pushing PH2 screw driver with the whole body weight while holding the plastic cover firmly. Once they are loosened use a fine screwdriver (smaller than PH1) to push the clips fully out of holes, again holding the plastic cover firmly. You won't damage the plastic cover or the clips this way.

goninanbl00d wrote on 2017-01-04, 02:38:

You do need to apply a significant amount of force to push the pins through the holes. […]
Show full quote

Eendje wrote:

I alteady tried to push those 'fingers' through the holes. But there was no movement. I was reluctant to push harder, afraid of damaging something. If you are sure that this is the right method, then I will apply more force tomorrow.

You do need to apply a significant amount of force to push the pins through the holes.

What I'd used to do was to sit a standard 6-32# case screw in the mounting hole against the pin, and then push down on the heatsink with the processor against a hard surface (such as a table). You'll hear a loud 'click' when the pin pops out.

It takes a significant amount of force (hence why you should push the processor against a table, instead of trying to hold onto the processor while pushing the pin through), but if you push down evenly on both sides of the heatsink you can avoid warping the processor PCB. The best part about this is it doesn't damage the clips -- you can re-use them if you need to.

I just want to thank you that this method saved my day. I unmounted three heatsink with this great screw and it works flawlessy without broke anything! THANKS!

I just want to say that finally I made a video explaining the procedure. I hope it really help you, finally a nice method to remove those crappy heatsink!

https://youtu.be/nXR42kt8ykc