How accurately sized do replacement thermal pads need to be?

[Mjball]

I'm just getting around to replacing the thermal pads in my GPU due to some crazy high hotspot temps, but when I was looking at the thicknesses of thermal pads I need, it's a ton of different, very specific sizes. If I'm reading it right, I need thermal pads with thicknesses of 0.8, 1.0, 1.5, 2.0, 2.25, and 3.0mm. Does it matter if I use a 1.0 for a 0.8, a 2.0 for a 2.25, etc.? I'm struggling to find some of these specific sizes, and I'm not sure how accurate I can be to the specifications. Even if I can find each size, it'll probably cost way more than it should having to buy that many sizes separately.

[OddOod]

From my understanding it's kinda important. Though, if you want you could try out some of that K5 Pro thermal pad goop

[Poinkachu]

53 minutes ago, Mjball said:

I'm just getting around to replacing the thermal pads in my GPU due to some crazy high hotspot temps, but when I was looking at the thicknesses of thermal pads I need, it's a ton of different, very specific sizes. If I'm reading it right, I need thermal pads with thicknesses of 0.8, 1.0, 1.5, 2.0, 2.25, and 3.0mm. Does it matter if I use a 1.0 for a 0.8, a 2.0 for a 2.25, etc.? I'm struggling to find some of these specific sizes, and I'm not sure how accurate I can be to the specifications. Even if I can find each size, it'll probably cost way more than it should having to buy that many sizes separately.

IMHO, it should be fine if it's just 0,1 to 0.25mm difference, especially if the pads is the really squishy type.

 

No idea who measured the pads in that google sheet, but there is a chance s/he measured the old pads and therefore measured a squished/malformed pads

[Brian McKee]

It is extremely important. Too thick and you risk damaging components due to higher pressure, too thin and you're not making contact. This is why I usually use K5 pro if I can not accurately determine pad thickness for a device or find proper pads.

[Salted Spinach]

It depends on the flatness and uniformity of the IHS and heatsink surfaces. If IHS is very convex or the cooler's contact surface is of poor quality, you are going to want a thicker thermal pad to fill in the bigger gaps

 

Unfortunately it is not reasonable for the consumer to measure this due to the equipment required. Best you can do is look up reviews on the cooler and/or user feedback of the particular thermal pad thickness for the generation of CPU you are using

 

Edit: I misread the OP as CPU thermal pad

[Brian McKee]

Just now, Salted Spinach said:

It depends on the flatness and uniformity of the IHS and heatsink surfaces. If IHS is very convex or the cooler's contact surface is of poor quality, you are going to want a thicker thermal pad to fill in the bigger gaps

 

Unfortunately it is not reasonable for the consumer to measure this due to the equipment required. Best you can do is look up reviews on the cooler and/or user feedback of the particular thermal pad thickness for the generation of CPU you are using

This is GPU repadding. Usually for VRMs and such.

[Salted Spinach]

6 minutes ago, Brian McKee said:

This is GPU repadding. Usually for VRMs and such.

Ah, my mistake

 

For the GPU, I would just buy 2-3 different thickness and start with the thinnest.

1. Place the pads and mount the cooler.
2. Unmount the cooler and look for an impression on every pad
3. Those that do not have an impression, replace with a thicker pad
4. Repeat steps 1-3 until there is an impression on every pad

Often the ideal situation involves use of pads of varying thickness, as you might have noticed when disassembling the card for the very first time