If you’ve ever had to remove a CPU and heatsink, you may have ended up with the CPU stuck to the cooler.
For some reason, the thermal paste some CPU use has a nasty habit of sticking so firmly to the CPU that removing the heatsink often pulls the CPU out of the socket along with it.
And you end up with the CPU stock to the bottom of the heatsink so strongly that it appears to be permanently welded there.
In this article, and with the help of my friend (who’s an expert in these things), I will explain why this happens and how you remove it without damaging the CPU.
Why Does This Happen?
When repairing personal computers, laptops, and servers, it is often necessary to carry out preventive dust cleaning with thermal paste replacement.
As you may know, a dried thermal paste can fasten the processor to the heatsink quite firmly.
This problem is especially acute for older PCs and pin connectors. The heatsink is removed with the processor when you want to remove the heatsink to replace the thermal paste.
Of course, the most thoughtful way to separate the heatsink is to gently rotate it along the plane of the motherboard while the processor is still in the socket.
However, such a trick does not work with a cooler in which the radiator mounting system has a bounding box or capacitors close to the socket – here, it will not work to crank the radiator.
Things to Watch Out for
The worst thing about this situation is that the processor is a delicate enough device to beat it with a hammer or chisel from the heatsink. Therefore, it is necessary to act very carefully here.
So, first of all, what you want to do if this happens, you want to check to make sure that all the pins are nice and straight.
Because depending on how when you unhook this and you pull this out, sometimes if you pull straight up, you’ll be lucky, like with this one, that they’re all straight.
- If you pull it up sideways or to the side, some of the edge pins will get bent, and you’ll have to bend that back. You got to be really careful, so you don’t break them.
I advise you not to touch the legs of the processor because bending them is easy but takes a very long time to align.
- It’s also not necessary to heat a processor with a heatsink, for example, with a gas burner, hoping to soften the thermal paste – the dried thermal paste will not become softer, and it is not so easy to heat a massive heatsink.
For this not to happen: you run your computer, run a benchmark, so it gets hot enough, let it sit for a bit, and then remove it.
So how to get this off? The easiest way possible. There are actually three ways to get this off pretty quickly.
Unstucking the CPU Using Basic Chemistry
Everyone knows thermal paste is well washed off with alcohol or a solvent.
Therefore, I advise dissolving the thermal paste if the heatsink has been removed with the processor.
First, we’ll clean the excess thermal paste at the junction of the processor and heatsink.
We then drip alcohol or solvent around the perimeter of the processor so that it flows into micro cracks in the thermal paste under the processor.
This should be done methodically for 10-15 minutes. Then, as soon as the alcohol evaporates – drip more.
Then we gradually soften the thermal paste due to the penetration of alcohol into its microcracks.
How not to break the processor
The most important part is to rotate the processor along its plane slightly.
You can’t hit the end of the processor, and I also don’t recommend resting until the processor rally. Otherwise, it falls far, beats against a hard surface, and bends the legs.
And it will take much longer to straighten the legs than 15 minutes, and even on a sober one – with no trembling hands.
You can use a long wooden handle of an art brush, which I use to clean dust from hard-to-reach places in household appliances.
Using the heatsink mount as a stop, you need to press slightly on the end of the processor with a wooden handle. As soon as the processor moves a little, loosen the force, but proceed in the same direction.
And so on until the processor is completely removed.
Looking at the dried thermal paste, you can understand what was happening under the processor – the alcohol will slowly soak the thermal paste until it becomes soft.
Dark spots on the thermal paste will be places where alcohol will crawl through.
Then everything is simple – clean the processor and heatsink from the dried paste. Everything should shine.
You Can Also Use Dental Floss
One of the most popular methods is also dental floss. I use it fairly often at home.
So what you do is:
- You take a little bit of your dental floss, and you work with it the same way that you would do with your teeth
- You start in one of the corners and then start working your way.
Most of the fans have four screws. So you can take off four screws and heat it up for a bit to get this thermal paste.
Heat up to a point where it won’t stick, or it won’t be huge of a problem to remove it. Then, make sure you get underneath the processor.
If someone tells you to use pliers, tweezers, or anything like that to remove this, you better not listen to them.
This is easier said than done because the majority of the time is truly stuck on there. So you just have to keep going until you succeed.
Using a Hair Dryer and a Blade
First, you need to apply heat. The easiest way to do this is to use a hair dryer.
This makes the thermal paste more malleable and easier to unstick. The heat sink should be slightly hot to the touch but not uncomfortably hot.
Next, you need a flat blade – for example, a box cutter.
- With one corner of the CPU facing you, slide the blade along the surface of the heat sink until it makes contact with the corner of the metal heat spreader on the CPU.
- Now, with one thumb on each side of the blade, press gently forward while rocking the box cutter from side to side.
You should find pretty quickly that the blade will slide under the corner of the heat spreader, and now it should be easy to slide it further underneath until it separates from the heat sink.
Put the CPU straight back into the plastic tray it came in to preserve the pins and wipe off the excess thermal paste with a QTIP or a cotton pad dampened in Isopropyl alcohol.
Once you’ve removed most of the thermal paste, you can switch to a QTIP dampened in some thermal surface purifier to clean.
How to Apply New Thermal Paste
We install the processor in place in the socket. In some cases, cleaning the insides of the server will be required.
Now the question arises – how to evenly apply thermal paste on the processor so that the thermal contact is as good as possible?
For this, many experts use an old plastic card or a small construction rubber spatula. It turns out pretty nice. Not to say that it is perfectly even, but beautiful.
We apply the same layer to the copper radiator. The most important condition is that the thermal paste should be as fresh as possible to better spread under the heat sink pressure on the processor.
Let me remind you that too much, or too little thermal paste negatively affects thermal contact.
It should fill the unevenness between the surface of the processor cover and the surface of the heatsink. All excess thermal paste is usually squeezed out of the thermal contact area.
If it stays there, there’s nothing to worry about. It may even increase the thermal contact area by a couple of percent.
But what about NO thermal paste? Will CPU then work? If you are interested, make sure to read Does CPU Need Thermal Paste? (Tested)