I think if you get putty you won’t need the exact size

 

I'll look into that! I was only aware of thermal paste and pads. That seems like it might be the solution.

 

Since you have the original heat sink, if you have a caliper, you can try this:

 

I would think an email to MSI customer support would be the way to get a correct answer to the question.

 

these companies have a bad habit of replying "disassembling the card will void the warranty, therefore we will not give you this information"

even though voiding the warranty is not true. got to love it.

 

I did end up getting a diagram from MSI. This is both for the gaming trio and gaming X trio as they both have the same cooler layouts.

 

Since I Have this card: man this is going to suck. You can't find 1.25 and 1.75 easily, and the 20W/mK ones are really too firm. So I guess a soft 1.5 and 2.0

Also I wouldn't really bother with anything but the VRM power stages and the VRAM. Inductors and backplate are irrelevant.

 

Im just going to use thermal putty. It looks a lot easier to work with and not make a mistake leaving gaps etc. I should have asked this before buying but whats the ideal thermal conductivity? I got some thats 12.8 W/mK