New Mac Pro is the machine we have all been waiting for, great engineering, wonderful craftmanship, everything is great, except well, price. 🙂 I believe some of you would like to save some money, and buy and upgrade your Mac Pro 2019 yourself.

Here is the quick guide on how to replace CPU in Mac Pro 2019.

I believe CPU upgrade will become more popular with years to come since price of the CPUs will fall greatly, and there is a lot of power to be gained from this upgrade.

I got basic version of Mac Pro 2019, and decided to upgrade it myself. By default (in 2020) it ships with 8 core Intel Xeon W w-3223 CPU. CPU is on a socket FCLGA3647. So, you will need CPU that fits that socket. CPUs from Intel Xeon W series is what I was looking for. Perhaps Intel Xeon CPUs also would work, but that is out of the scope of this quide.

Here are the details on CPU that my Mac Pro came with –

What I got is Intel Xeon W-3245 –

It is 16 core CPU that fits same socket and is from the same series. CPU is currently at around 2.400,00€ here in Europe.

Anything above that core count doesn’t make sense for me, since prices are rocketing per core, and my workloads will not benefit from more cores.

One thing to have in mind if you are reading this and still haven’t got a CPU – if you need specific amount of RAM – lets say – 1TB of RAM – you will need 24 or 28 core CPU.

There are limits for RAM configurations based on CPU you select. 8-core CPU supports 768GB of RAM in quad channel, 12-16 core support 768GB of RAM in six channel config, and only 24-28 core CPUs can support up to 1.5TB or RAM.

Now, onto the guide for changing CPU. Before we start – I cannot take responsibility for any damage you do following this guide, be it physical or emotional distress you may feel ruining your machine. It is all up to you. You are doing it at your own risk, and do not attempt it if you are not familiar with basic computer hardware tasks.

Replacing CPU

Tools Needed


I won’t get through the procedure of opening Mac Pro 2019 – it is simple enough. Disconnect all the cables (especially power) open the cover at that should be it.

Before we start make sure you have a screwdriver with T15 Torx bit. You will also need long screwdriver with T15 Torx, screwdriver should be at least 30cm long so it can reach the screws at the bottom (12 inch).

Here is what I have (if that will help you). I have screwdriver handle, to which various shanks can be attached

Screwdriver handle (Wera 073240 821/1)

Attached to this is 30cm extension shank (forgive me if I have a wrong term, I don’t use these tools often). Wera 899/4/1S (300mm)

And you will need T15 Torx bit for that kit.

This is not in any way sponsored, this is what I had at hand, and if it will help someone – great.

Any screwdriver will do, make sure it is just long enough and you can attach Torx bits to it.

Thermal paste

I had Thermal Grizzly CPU thermal paste, but any CPU thermal paste will do, as long as it ok, and haven’t lost its cooling properties.

Cloth and isopropyl alcohol

Also having isopropyl alcohol and cloth or paper towels for removing thermal paste would be good.

Dismounting Passive CPU Cooler

This is the part where you will need your Torx screwdriver.

After you opened your Mac Pro 2019, you will find massive CPU cooler in the top left corner (in the red square on the picture) with Mac Pro engraved on it.

There are couple of screws we need to remove from the sides of the lid which has “Mac Pro” engraved.

There are two torx screws at the bottom part – unscrew them.

Also at the top of the case there are screws which you have to unscrew to remove the lid.

After you unscrewed all the necessary screws, you will be able to slide of the lid.

For the next part we will need long screwdriver I mentioned in the begining.

There are two holes at the top of the cooler.

Attach T15 Torx bit and make sure you have magnetised shank or torx bit so you don’t lose it on the way and can pull out the screw.

Shank should reach the bottom – torx screw.

If you succeeded, you will pull out screw that looks like this.

Ok, repeat the process for the second screw.

After both screws are out, our passive cooler is now free. You will now slide it up, because outer part is on a kind of rail. Make gentle moves, because there is a chance that CPU is stuck to the cooler. So, be very careful, don’t force anything.

OK, if you done everything correctly so far, you will be see your CPU covered in thermal paste.

Also, passive cooler you removed should be covered with thermal paste.

You will need to clean both. You can use just cloth to clean it (use gentle materials) or better yet, clean it with isopropyl alcohol. Make sure you clean everything in a way you don’t damage motherboard or other components!

Remember how this thermal paste looks, so you will know how to apply new thermal paste. Not too thick, or thin – it will also need to cover cpu and passive cooler same (or better) as this old paste.

! Few important warnings before we proceed further. Remember where is triangle on the CPU you are pulling out of the CPU socket. Do not leave CPU socket exposed for long time, make sure you have new CPU at hand to replace it immediately.

Remove any source of dirt, and anything that could fall onto exposed CPU socket before you lift CPU from socket. If you bend or break pins in CPU socket, it is game over, most of the times you will need new motherboard. In this case it will be huge expense.

Also, do not force anything. Gently pull CPU out, and gently put new CPU in.

Before you place new CPU in socket, triple check that it is turned correct way, and that four corners of the CPU socket match how the CPU looks underneath.

This is how my CPU looks like, also, you can see a red triangle, I marked in the red at the top right corner.

Ok, this piece of wire on top of the CPU is easily removable, you do not need to unscrew anything, just gently pull it out and it will come lose. Main thing is not to force it so you don’t break something, be patient and gentle.

I’m not sure I will explain it the best way, but I’ll try. In step 1, pull out in the way arrow is pointing. After you have that part out and freed, proceed to step 2 and gently pull in the way arrows are pointing, it will also set loose.

This should be result, wire bracelet is off the CPU, and CPU is now free.

Now, gently remove CPU. This is how your motherboard will look like now.

I have my new CPU ready, as I already told, I will be replacing 8-Core CPU W-3223 with 16 Core CPU W-3245

Now, reverse steps – place new CPU (very carefully, and make sure you place it right way, as I already described), put thermal paste on top of it – if you are not sure how, here is one nice tutorial/test – 

I usually put 5 dots. Just make sure you don’t put too much as it will spill all over the CPU.

Put in place metal wire over the CPU, and in the end put back passive cooler, make sure everything is tight, but not to tight, so you don’t break something.

That should be it. I did this three month ago, and I’m putting up this tutorial only after I’m sure that everything is ok. My Mac Pro works great without any problems, and I use it for 10 hours every day.

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