XFX 6800XT custom cooling (Why Manufacturers use 3 FANS?)

[vlad_8011]

Hi.

So i made custom cooling after series of tests for my 6800XT from XFX with NOCTUA NF-S12A PWM CHROMAX.


This is second Radeon 6800XT which i modded in same manner, previously i did same thing on Red Devil Limited Edition, with worse resoults - card was noisy, as there was audiable airflow through heatsink fins.
With XFX Merc that problem is not existing, which is kind of strange - heatsink is same size, with fins in same distance from each other. Funny thing - whole process was so simple, that even kid would do it - 6 screws and fan connector - done - whole plastic cover with fans was taken off:

Then, putting fans on zip-ties with VGA 4pin-4pin PWM adapter from Gelid + noctua fan splitter PWM (which cause some problems, as one part of splitter is only 3 pin, while plug is made for 4 pin) and 4pin PWM extender cable - done:

You may think how ugly it is - and so i am. I dont quite understand today FASHION (beacuse thats all that is) of 3 fans and long-as-hell radiators GPUs. In Red Devil with same fan config card was so on quieter than with original fans, while temps were much smaller. In XFX Merc we are talking about ~20 degree difference and (dont have noise meter) much quieter work.
So that screen shows full fan speed and its resoults on noctua fans, before i managed PWM control on GPU (i had to swap splitter extensions with fans, as one had 3 pin and PWM wasnt working despite the fact, both fans are 4 pin PWM)

Same setting, same test on original fans (ofcourse dont have screenshot to prove....) had much worse resoults. As you can see from above, i made some undervolting - 970mV, max VRAM freq. 2000MHz, max core clock 2200MHz, default power setting. I made those undervolt to comfortably sit nest to my PC, while original cooler from GPU was mounted.
I dont use hadphones, my ears are very sensitive to PC noise and i couldnt stand how loud was Red Devil and XFX Merc - just beacuse they rather to look good, than work good (that stupid fashion). I watched milion times reviews of that cards, and every noise test was completly out of ***. Before 6800XT Merc i had 6800 (non XT) merc - same noise, so its not that particular example - all thise cards are noisy as hell. Nothing reflect their noises as fans are relatively quiet - except airflow guide through heatsink fins. Small high pressure fans + tight fitted fins = you got noise.
As i proven second time, you dont need extra long heatsink with part of it, extending above PCB lenght with just big hole in it. You dont need 3 fans, from which one is allways louder over time as its smaller. Hell, you dont even need slim fans!
All i respect was XFX addiction to ease of removing (and replacing) fans, beacuse whole heatsink is almost flat, which on Red Devil was nightmare, as there was lot of molded fan cable holders and fans needed to be on extra spacers (rubber ofcourse).

Here is processhow it looked onRed Devil:

Unfortunely, Radeons and lots of new RTX 3000 are not possible to mount vertically, not sure why - people say its beacuse heatpipe design (beacuse they are turning right after cold plate, which is common, and was present in GTX 1080TI, which was working properly....), but i'm sure there is more behind it. So i made several tests with fans 2 x 120mm (mounted to proforated PSU shroud) blowing on original cooler, then blowing on naked heatsink (without original fans), then mounted to heatsink in verticall and horizontal position, and only in horizontal position it give great benefit.
Currently Radeon is audiable on 1100+ RPM, which is no need to use, as card keep great temps up to 900RPM while gaming.

 

[notarat]

Very good write-up on what you did. thanks for posting lots of pics of the process as well! Nice job!

 

[Nobu]

The shroud would be 0.5" taller with fans that thick, so they probably went with thinner fans to save space. Shorter fans need to spin faster to move the same volume of air through a restricted passage, so they probably added fins and a third fan to improve acoustics and cooling performance.

That said, those compromises are certainly not necessary in every case.

 

[cybereality]

I have the Merc. The design is why I liked it so much, the shroud and backplate are preem.

And it's been almost silent for me, but I can understand wanting better performance. Nice job.

 

[Gattlin]

Hi.

So i made custom cooling after series of tests for my 6800XT from XFX with NOCTUA NF-S12A PWM CHROMAX.
View attachment 382197View attachment 382198View attachment 382199View attachment 382200

This is second Radeon 6800XT which i modded in same manner, previously i did same thing on Red Devil Limited Edition, with worse resoults - card was noisy, as there was audiable airflow through heatsink fins.
With XFX Merc that problem is not existing, which is kind of strange - heatsink is same size, with fins in same distance from each other. Funny thing - whole process was so simple, that even kid would do it - 6 screws and fan connector - done - whole plastic cover with fans was taken off:
View attachment 382193View attachment 382194
Then, putting fans on zip-ties with VGA 4pin-4pin PWM adapter from Gelid + noctua fan splitter PWM (which cause some problems, as one part of splitter is only 3 pin, while plug is made for 4 pin) and 4pin PWM extender cable - done:
View attachment 382196View attachment 382195
You may think how ugly it is - and so i am. I dont quite understand today FASHION (beacuse thats all that is) of 3 fans and long-as-hell radiators GPUs. In Red Devil with same fan config card was so on quieter than with original fans, while temps were much smaller. In XFX Merc we are talking about ~20 degree difference and (dont have noise meter) much quieter work.
So that screen shows full fan speed and its resoults on noctua fans, before i managed PWM control on GPU (i had to swap splitter extensions with fans, as one had 3 pin and PWM wasnt working despite the fact, both fans are 4 pin PWM)
View attachment 382192
Same setting, same test on original fans (ofcourse dont have screenshot to prove....) had much worse resoults. As you can see from above, i made some undervolting - 970mV, max VRAM freq. 2000MHz, max core clock 2200MHz, default power setting. I made those undervolt to comfortably sit nest to my PC, while original cooler from GPU was mounted.
I dont use hadphones, my ears are very sensitive to PC noise and i couldnt stand how loud was Red Devil and XFX Merc - just beacuse they rather to look good, than work good (that stupid fashion). I watched milion times reviews of that cards, and every noise test was completly out of ***. Before 6800XT Merc i had 6800 (non XT) merc - same noise, so its not that particular example - all thise cards are noisy as hell. Nothing reflect their noises as fans are relatively quiet - except airflow guide through heatsink fins. Small high pressure fans + tight fitted fins = you got noise.
As i proven second time, you dont need extra long heatsink with part of it, extending above PCB lenght with just big hole in it. You dont need 3 fans, from which one is allways louder over time as its smaller. Hell, you dont even need slim fans!
All i respect was XFX addiction to ease of removing (and replacing) fans, beacuse whole heatsink is almost flat, which on Red Devil was nightmare, as there was lot of molded fan cable holders and fans needed to be on extra spacers (rubber ofcourse).

Here is processhow it looked onRed Devil:
View attachment 382220View attachment 382219View attachment 382218View attachment 382217View attachment 382216View attachment 382215View attachment 382214View attachment 382213View attachment 382212View attachment 382211View attachment 382210View attachment 382209View attachment 382208
Unfortunely, Radeons and lots of new RTX 3000 are not possible to mount vertically, not sure why - people say its beacuse heatpipe design (beacuse they are turning right after cold plate, which is common, and was present in GTX 1080TI, which was working properly....), but i'm sure there is more behind it. So i made several tests with fans 2 x 120mm (mounted to proforated PSU shroud) blowing on original cooler, then blowing on naked heatsink (without original fans), then mounted to heatsink in verticall and horizontal position, and only in horizontal position it give great benefit.
Currently Radeon is audiable on 1100+ RPM, which is no need to use, as card keep great temps up to 900RPM while gaming.

I have a GTX 1080 ti mounted vertically .Right now the temp reads 29c in a 22c ambient but it reaches up to 58c when pushed hard with an aggressive fan profile .

 

[pippenainteasy]

I mean you basically did what most people do in mini ITX setups, shorten the shroud and attach aftermarket fans. It often works better than using stock fans + thin intake fans, and instead just have thicker 25mm fans.

 

[ChosenUno]

The problem with your setup is that it's a 3 to 4 slot design, while most GPU mfgs want dual slot at most.

Have you thought about using slim 120mm instead?

 

[Riptide_NVN]

The problem with your setup is that it's a 3 to 4 slot design, while most GPU mfgs want dual slot at most.

Noticed that too. Thing is huge lol.

That said even my powercolor 5700xt has a 2.5 slot design and my asus tuf 5600xt is a 2.7 slot. Going over 2 slot designs has been a thing for a while now.

I never understood x-fire and sli when those cards would be sandwiched so close together on most motherboards. Unless you're using a blower card it's a recipe for heat problems.

 

[vlad_8011]

Gattlin - i had same temps with GTX 1080 Ti gaming X Trio - it was very cold GPU, yet pretty quiet - on original fans.
@trandoanhung1991 - i would gain 1-1,5cm clearance, but that wasnt needed in such big case (note motherboard tray is 1,5cm above PSU shroud). Now i'm switched case For SS Alta F1 + RTX 3080 TUF - all my problems are solved But i dont regret this experiment, it works everytime.

 

[xx0xx]

Great stuff!

I did something similar with a noisy 750ti that even at minimum RPM (40% apparently is as low as these are 'allowed' to go) had a quite loud hum. I took off the shroud, zip-tied on a noctua fan with a 2-pin fan adapter, and now it is near-silent and runs just as cool at idle and load, if not cooler.

 

[WilyKit]

The problem with your setup is that it's a 3 to 4 slot design, while most GPU mfgs want dual slot at most.

Have you thought about using slim 120mm instead?

That’s probably going to change if the reports of 400-450 watt TDP for Ada Lovelace is accurate.

 

[vegan]

Given the power consumption 3 fans are needed as much as my old R9 Fury which was a 300W card

 

[ChosenUno]

That’s probably going to change if the reports of 400-450 watt TDP for Ada Lovelace is accurate.

Well, remember PowerColor had a 295x2 Devil 13 air-cooled edition. 3-fan, triple-slot monster that managed to cool a 600W total TDP dual GPU cores, and still managed below 90oC temps. The card was massive at 3kg, so it came bundled with a support jack.

 

[WilyKit]

Well, remember PowerColor had a 295x2 Devil 13 air-cooled edition. 3-fan, triple-slot monster that managed to cool a 600W total TDP dual GPU cores, and still managed below 90oC temps. The card was massive at 3kg, so it came bundled with a support jack.

I think part of the problem is the energy density of newer GPUs. It’s easier to pull 600 watts from a larger area than it is to pull it from a more compact area which is what we get as the transistors shrink in size.

 

[ChosenUno]

I think part of the problem is the energy density of newer GPUs. It’s easier to pull 600 watts from a larger area than it is to pull it from a more compact area which is what we get as the transistors shrink in size.

Oh you mean the dark silicon problem?

I think that'll require a huge rethink in IHS design, it's not gonna be the cooler's problem. We have proven air coolers for GPUs that can dissipate 600W, so the question now becomes how to spread all that heat from the die over to the IHS as efficient as possible. Maybe some application of graphite there might help?

 

[vlad_8011]

It's been long time, and lot have happen. I had to change case from Silverstone Alta F1, as it almost killed RTX 3080 TUF - there is no sensor over back VRM (closer to video outputs) but noticed compression of thermopad there and RMA did not helped. So I swapped GPU to XFX 6800 XT, but this time that was CORE, and 3 in the row had coil whine. After month of different testing I'm sure that was GPU's.

So I ended up with 6800 XT Gaming Z Trio,

it's hard to describe, but MSI really messed up! I made similar swap with fans, but that worked only for noise, temps are the same. I got 30+ degree delta between edge (core) temp and junction (hotspot). This is becoming worse with every year, quality is decreasing to worst I ever seen.

I have to keep the GPU, it's been 2 months since I bought it, I can't sell it (even 250 USD cheaper), can't OC it, can't UV it (it's really bad silicon, it won't go under 1100mv) and temps aren't that great (around 70 degree C). So this time It didn't work out

 

[vlad_8011]

I swapped fans again, temps are best ever, but I guess it's mostly because if ati-sag handle, and to be precise - the place it hold the GPU.
Anti-sag handle, hold GPU right in the middle right now. I have noticed, whole heatsink holds on mostly near the GPU die, near the power inputs it's just floating - that's why giving the support on the GPU end (next to power input) was giving worse readings on temps. Heatsink is bending PCB or have not enough tights on screws, making not even pressure over GPU die.

GPU is now slightly cooler and still unmatched quiet. Heat from heatsink is not pushed on tempered glass panel, but into the top.

Funny thing - backplate can be taken off, I did it because I noticed (since I bought this GPU) that termopads above VRAM have no contact with PCB - just floating above it with about 2mm gap. I looked from different angle and backplate have been bended beacuse of matt plastic cover for LED strip. It just keeps backplate too much bended upwards. I tried to push backplate to make it straight but was little worried it won't break - it's not metal, more plastic (MSI says it contain graphen).

Overall I'm pretty happy with the result and leave it that way. I also like the look of it right now, dual 140's greatly covers heatsink and don't need any cover. Now I also want to increase height of my case - use higher feets, as it's definitely not enough space underneath it for air to be sucked inside.

So one more proof - 3 fans are not needed. If rumors will be real about Ada Lovelace, that will be only solution for 4090 (and maybe 4080 too) to keep low noise level and good temps. I wish manufacturers will understand it finally.

 

[pendragon1]

ive done this with plenty of cards and it works so good asus came out with their noctua rtx 3000 line.

 

[Furious_Styles]

ive done this with plenty of cards and it works so good asus came out with their noctua rtx 3000 line.

Same, been doing this for years now. Really made a difference on this zotac 2080 ti that had a dual slot cooler. It pretty much solved all throttling issues the card had.