EVGA_JacobF
They vary in size depending on the location.

hallowen
It is hard to get an accurate measurement of the TIM pad thickness on my EVGA RTX 3090 FTW3 Ultra when I removed the heat sink assembly for the purposes of re-applying the GPU TIM.
The Memory TIM pads are of a very soft consistency and can be broken/stretched or marred when removing if you just try and pull them off.
As shown in the photos, I managed to lift them off with a wooden flat stick, But not without causing damage to the soft putty like TIM.
As far as that super soft putty that was "pasted" between and on the VRM's, I just cleaned all that off with Isopropyl alcohol and used some 1mm TIM strips as a temporary "fix" until I run some VRM temperature checks and compare it to my SECOND FTW3 Ultra that I have not disassembled yet.
The photo of the back of the PCB with the Metal "heat sink" removed shows the memory TIM after I removed it with little damage to them because I did not try and remove them from the chips as I did on the front PCB components.
 
 

EVGA_JacobF
Memory is 2.25mm, VRM 2.85mm, back VRAM is 2mm

zurvv
Some pad updates.
Note, i used fuji ultra extreme - which doesn't compress much. So it isn't useful to compare the below info to other more squishy pads (like the ones that came with the card)
 
I replaced the putty and use a .5mm pad. It made contact. (i also put a layer of TIM too.)
For the ram i used a 2mm pad (1.5mm plus a .5mm - there wasn't a fuji  extreme 2mm option)
 
First, ram and the rest of the card pretty well cooled. I never saw the ram hit more than 70C. (with 30min load of timespy extreme with +750.) That is read from the ICX3 sensors. 
The problem is the GPU, it is hotter than it was before (and thus didn't OC was well.) I'm not sure which of the pads is causing the problem (my guess would be the ram)
 
*sigh* those fuji's cost a ton. I'll most likekly have to replace it was a 2mm pad that has more give. I have some TG pads around.
 
I also put TG pads on the back of the card on the ram. 2mm is right.
For other parts of the card i needed 2.5mm to make it to the PCB. (i put pads on the back side of the VRMs)
 
(for TIM on the GPU i used TG Kryonaut Extreme)
 
 
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UPDATED:
I replaced the fuji ultra extreme with TG pads (which compress better.)
My size suggestions for replacing pads with using TG
 
2mm for ram, .5mm for putty replacement, 2mm for ram on the back. 2.5mm for PCB to back.