Hi. I saw The_Scarlet_One's post about thermal pads awhile ago. Here is the quote I wanted to post about.
 
"The thermal rating on the pads has shown to be less honest than what most assume, from what I have been reading lately. I guess the company can use their own specific testing methods to make their product look better. I noticed that people (to include myself) have purchased the “extreme 17w/mk fujipoly thermal pads” just to find out they perform almost exactly the same as the 5w/mk pads because all of the other surfaces become limiting factors."
 
I have a EVGA 3080 FTW Ultra that I am putting a water block on. I was trying to get the Optimus WB first but that guy is unreliable yet according to him he has alot of science knowledge, putting together mars rover and stuff (Something like that). The Fujipoly pads across the entire backplate caught my eye on the Optimus WB. I am going to do the same thing but Im at a fork in the road over AYIYUNNI 7w on the entire backplate versus Fuji 17W (maybe 11W) (across the backplate where the gpu, vrm and mosfets are) and AYI 7w over everything else. What am I trying to achieve? Well I am putting it together right now so if I can do a few extra little things to get the lowest temp thats okay with me. If money is no issue what is your recommendation? Based on what Scarlet has said in the past, you might say just get the AYIYUNNI, just wanted to double check. First water cooling build btw.
 
Thanks.

As someone with thermal-taped heatsinks on the backplate of their Kingpin (with more arriving tomorrow to make it look like a proper heatsinked monstrosity), I cannot comment on what the best option would be, but I am very interested in the result of your efforts & wish you luck on your first liquid cooling journey.
 
I would say get the Ayiyunni myself, the backside of the 3080 is mostly dissipating PCB heatsoak and the heat generated from the components in the immediate areas above them - it will help in some areas quite a bit, and do just about nothing in others.  If it were a 3090, this would be an entirely different conversation.
 
Will keep an eye on this thread as well because I plan on going a full block on my card later on as well, probably... and if I do, that backplate gonna get the works lol

Dabadger84
 
 
I would say get the Ayiyunni myself, the backside of the 3080 is mostly dissipating PCB heatsoak and the heat generated from the components in the immediate areas above them - it will help in some areas quite a bit, and do just about nothing in others. 

Thanks. Im assuming the parts of the PCB that dont get hot and have the thermal pad over them will just heat up from the heat spreading thru out the pad. since heat travels to colder areas

 
Neverminding the black-blob there from the LED area's stuff - the main heatsoak/heat generation elements on the back are going to be all of the areas you'd expect, I boxed them:
 

 
So pretty much everywhere. lol
 
That's basically what I'm planning on doing to my backplate, with the thermal tape heatsinks, when it's all said & done, I'm going to have 20x20x10mm heatsinks in a row on the VRM areas (the big boxes) and then the rest of them clustered on the vRAM & above the GPU die area, like the boxes:
 

 
Just what I have on there now has already dropped 4-6C off my load temps on 2 of the 3 memory iCX sensors, as well as dropping my Memory Junction Temp a few degrees, and other temps 1-3C as well, which is pretty crazy considering how little I've done so far:
 

 
Just those with a fan blowing over them has made that difference - granted, the 3090 is a whole 'nother beast because of the vRAM chips being on the back of the PCB too, but I imagine it will still help with the 3080's thermals to have more heat dissipation like you are planning to do.

Iv got a 3090 and just pumped the whole back plate full of thermal putty up to the LED and slits in the PCB.
But that was mainly because using the pads that came with EKWB back plate amplified the coil whine.

@dabadger
Funny, when I first read your post I started looking up heatsinks to put on the back of the pcb, full length too. But I stopped because I realized how am I going to glue it to the backplate. I see you used thermal tape. I gotta research that.
 
This is how I imagined it. Maybe its a bit naive. I know the whole backplate gets hot not just one area but maybe the temps are lower toward the edge which can allow more head dissipation from MOS, VRM, etc... if you have a full length thermal pad.
 
 
@bmgjet notice any difference?

That's fairly accurate, the warmest areas of the back of the card & thereby the backplate would likely be the backside of the VRMs, & the GPU die area.  The vRAM on the 3080 not being double-stacked on either side of the PCB like it is on the 3090 makes them slightly less of a heatsoak source.
 
It would be interesting to see what good some thermal pads or tape with heatsinks would do on the backplate of a 3080 though.  Imagine it'd be a less dramatic effect, but still a help.
 
With the 3090 Kingpin specifically, the backplate is thicker, but from what I understand (I haven't removed my backplate but I've seen stuff from people that have) there's thermal pads between it & the vRAM chiplets, and some other areas.  I'd love to see an image of what exactly the stuff looks like freshly after it's been pulled off the card the first time, unfortunately we never got a "disassembly" video from Gamers Nexus or anywhere because Kingpins were thrown straight at LN2 by most YouTube Reviewers - which is fair enough, but still, disappointing for me.
 
Based on what I've seen from what I already have on there, where some temps are going down more than others, I'm thinking adding the additional heatsinks will further help with that.
 
The ones I'm buying have the thermal tape pre installed... the tiny ones I already have (Do not recommend buying, the ENTIRE pack is almost entirely in the picture I posted earlier of the backside of my card currently): https://smile.amazon.com/gp/product/B084X4VMP9/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1 and the ones I'm getting in tomorrow: https://smile.amazon.com/gp/product/B07BDKN3XV/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1 that are bigger also have thermal tape already applied.
 
I'm sure it's not as effective as paste or a thin, better-heat-conductivity pad, but I am not stickin' crap to my card with paste lol

kikkoman123
@bmgjet notice any difference?

It got rid of the coil whine.
But cant really compare numbers since I put it under water as soon as blocks were avaliable and that was before there was the vram temps avaliable in hwinfo and 3090 XC3 doesnt have any ICX temp sensors.

Dabadger84
Just what I have on there now has already dropped 4-6C off my load temps on 2 of the 3 memory iCX sensors, as well as dropping my Memory Junction Temp a few degrees, and other temps 1-3C as well, which is pretty crazy considering how little I've done so far:
 

 
Just those with a fan blowing over them has made that difference - granted, the 3090 is a whole 'nother beast because of the vRAM chips being on the back of the PCB too, but I imagine it will still help with the 3080's thermals to have more heat dissipation like you are planning to do.

How do you have those little aluminum heatsinks attached? What's your case cooling look like for airflow? I'd like to get my 3090 memory temps down, they are horrific. What did that get yours down to and at what memory speed? 
 
I'm tempted to give these guys a shot but not sure how I want to attach them. 

https://smile.amazon.com/...XKGXPP9Y1BT8&psc=1
 

osb40000

Dabadger84
Just what I have on there now has already dropped 4-6C off my load temps on 2 of the 3 memory iCX sensors, as well as dropping my Memory Junction Temp a few degrees, and other temps 1-3C as well, which is pretty crazy considering how little I've done so far:
 

 
Just those with a fan blowing over them has made that difference - granted, the 3090 is a whole 'nother beast because of the vRAM chips being on the back of the PCB too, but I imagine it will still help with the 3080's thermals to have more heat dissipation like you are planning to do.

How do you have those little aluminum heatsinks attached? What's your case cooling look like for airflow? I'd like to get my 3090 memory temps down, they are horrific. What did that get yours down to and at what memory speed? 
 
I'm tempted to give these guys a shot but not sure how I want to attach them. 

https://smile.amazon.com/...XKGXPP9Y1BT8&psc=1
 

I put a Hybrid kit on the back of my Kingpin and attached a chiller to it o.O