Hummmm.  You are missing a copper plate, around the AIO.

Uh ooh. Let's hope this is not a factory OOPSIE trend.

Bump...looking for the same information. My 3080 XC3 Ultra hybrid seems to be too hot on the VRAM. There's a 60 degrees Celsius delta between the GPU processor and nthe VRAM. GPU core is at 40 C and the VRAM is at 100 at full load. Something is certainly off. I'm thinking of replacing the pads. I can't believe it came from the factory like this, or this is the expected performance.

Hey so i know I have my copper plate installed in my 3080 ftw ultra but i see mem temps around 84 or so under full load with stock curve so my question is what is the thermal pad size ? because maybe I would like to switch the stock ones or re paste as maybe I messed up

WHAT SIZE ARE THE THERMAL PADS ON THIS THING !! IF WE WANT TO RE PASTE WE NEED TO KNOW! SOMEONE PLEASE HELP ME!!
 

I have a hybrid kit coming in the mail. I'll measure the pads with some calipers when it arrives. I have .5mm, 1mm, and 2mm Kryonaut minus pads on hand as well as some Kryonaut extreme. Want to get the best out of the hybrid kit as possible. According to EVGATech_LeeM here: (Edit: Won't let me paste the link to EVGA's own forum apparently so see below.)  the pads are an arbitrary size so it'll probably be a matter of going slightly oversized. But as I said I'll put some calipers on them when the kit arrives. 
 

Sorry for the delay; I wanted to confirm something with the HYBRID cards/kits.
 
3090/3080 FTW3 Pads:
 
1pcs: 7.7mm x 6.5mm x 2.75mm
2pcs: 53mm x 14mm x 2.25mm
1pcs: 37.5mm x 14mm x 2.25mm
1pcs: 15mm x 12mm x 2.25mm
1pcs: 110mm x 5mm x 2.5mm
 
 
3090/3080 FTW3 BP Pads:
 
2pcs: 51mm x 12mm x 2mm
1pcs: 38mm x 12mm x 2mm
1pcs: 14mm x 10mm x 2mm
 
 
3090/3080 FTW3 HYBRID/HYBRID Kit Pads:
 
Thermal pads for VRAM heatsink:
2pcs: 49mm x 13mm x 2.25mm
1pcs: 37.5mm x 12mm x 2.25mm
1pcs: 13mm x 13mm x 2.25mm
 
Thermal pads for standalone heatsink:
1pcs: 80mm x 4.5mm x 2.25mm
1pcs: 75mm x 11mm x 0.75mm - Note: This thermal pad is not initially on the HYBRID card.  Thermal putty is used in its place.  If you remove/clean the thermal putty, then replace it with a thermal pad of these dimensions.
 
Thermal pads for heatsink connected to the fan:
1pcs: 106mm x 5mm x 2.25mm
1pcs: 105mm x 11mm x 0.75mm - Note: This thermal pad is not initially on the HYBRID card.  Thermal putty is used in its place.  If you remove/clean the thermal putty, then replace it with a thermal pad of these dimensions.

My god. I give up with my idea to change my FTW3 Ultra to a Hybrid 

I'll just adapt to the noise ;)

Mining on an EVGA RTX 3080 Hybrid (stock hybrid, not a kit), I was seeing GPU=46C and VRAM=96C.  I replaced the VRAM thermal pads using 2.0mm Gelid Ultimate and replaced the thermal paste on the GPU and paste between the copper plate and water block with Noctua NT-H1.
 
With same OCs, 100% fans, ambient temperature, etc. settings, temps dropped to GPU=39C and VRAM=86C.  If I change fan control settings to keep VRAM<90C and leave everything else the same, then fans reduced to 60%.