Are we talking about memory temperature? At what load and at what overclock you have 50 degrees? What is your memory temperature when mining? Could you show me a screenshot from GPU-Z with all the sensors when mining?
The ideal method would be to measure the actual gaps accurately and make copper shims with thermal paste only. The 1.5mm copper with 0.5mm thermalpad method would also work.
Wow! What are your temperature results?
So, thermal putty arrived and I have changed both front and back on my PNY gaming, interestingly enough the stock pads on the front were 2mm. My cooler didn't have a detachable sub plate and the core/mem plate was a one piece unit with vapour chamber.
The putty was easy to install, no worrying to much about thickness or pad positioning, I just scooped some from the container rolled it into a sausage for the rows of vram, then flattened it out slightly to a thickness greater than the stock pads. cooler went on easily, no fighting to get it to seat etc I removed the cooler to check core contact which was perfect. Simply reshaped the putty and reinstalled. Same applies with the backplate.
I left all the stock vrm/choke/etc pads as is
Mem temps went from 108 to 90, with a 300mhz greater o/c. Now maxed out at 1500 in Afterburner. I was also able to remove some of the heatsinks from the back of the card.
Gaming the card now boosts to 2040Mhz on the core with a 1500MHz Vram clock and sits there locked. I have flashed the gigabyte 390W bios to it.
All in all, highly recommended and will be my go too for thermal pads from now on. It's really that much easier to use.
I still believe that the overall cooling needs work on the gddr6x, but it is new.