Cooling Improving Noise in Cerberus w/3080 FE

Kaiede

Chassis Packer
Original poster
Jul 16, 2019
19
6
I've had this build for a bit as a quiet gaming rig with air cooling:

- 5600X with Noctua C14S - Pulling through side vents
- EVGA 2080 Gaming Ultra (3-slot version)
- Two NF-A12x25s as intake on the bottom
- One NF-S12A on the top as exhaust (not much else fits due to the C14S positioning)
- 750W PSU pulling from front, exhausting upwards

Under full load, the loudest thing about this build was the coil whine with fans maxing out at around 900 RPM, and the 2080 tended to sit at high 60s while gaming. The CPU topped out in the mid 60s as well. So was pretty happy with how things turned out.

With the 3080 FE added in, I've been having issues dealing with the extra wattage, and the fan noise of the FE. CPU package is a bit warmer, but not by much, so not worried about that. But at stock, the FE will hit the thermal limit and get super loud. After doing some undervolting (and capping the max clocks), I'm at 1830Mhz drawing about 250W versus the ~305-315W @ 1920Mhz stock. So now I can keep the fans at under 50% if I'm willing to accept the GPU running at ~80C. Not at the stock thermal limit anymore, barely. But at least all the fans are back to maxing out at 900RPM or so, keeping things quiet.

It feels like I might be hitting the limits of what I can expect from a pure air-cooled quiet build with a high end GPU, short of finding someone willing to trade a partner card for the FE to shave a few degrees. But before I start mulling the idea of building a custom loop and giving up the simplicity of air cooling, maybe more experienced folks have some tips on how I can further improve things here?
 

MarcParis

Spatial Philosopher
Apr 1, 2016
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Thanks for the summon @thelaughingman !

As using C14S with side vents (and summon of @thelaughingman ) I supposed you have either Cerberus or Cerberus-X..:) (ok found Cerberus in title..:))

What is capital with RTX 3080/3090 FE cards is to monitor properlly GDDR6X temperature (warmest part of your GPU). You can use HWINFO64 to monitor it easily.
Second, specific for Cerberus, make sure to flip C14S fans as exhaust.
Please note that C14S will heat RTX3080FE backplate. I found best compromise to be 645LT with rear intake....but C14S setup as exhaust is not far behind.

https://smallformfactor.net/forum/t...erberus-x-complete-build-log.2007/post-241003

Please share also some photos of your build.
 
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Kaiede

Chassis Packer
Original poster
Jul 16, 2019
19
6
Thanks for the thread link. Reading through that answered the questions I had about your advice, especially the bit as to why the 92mm AIO.

So I did try swapping around the orientation of the C14S fan (EDIT: photo was taken before I swapped the fan). So far, it does seem to slow down how quickly the GPU hits max temp, but right now after a 15-20min soak at full utilization, it peaks out at around 78C with 77C being average (still at 1830Mhz). Memory peaks at 98C with 96C average. The CPU is now sitting at 70-72C instead of mid-60s, but I guess that’s a bit more expected since it’s venting air from the GPU now.

I am a bit concerned about the main motherboard power cable now that I’m paying closer attention. It does partially block one of the fans on the FE, although it doesn’t hit the fan at all. And yes, I am aware of the missing PCIe slot cover. I need to go fetch it out of the box.

 
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MarcParis

Spatial Philosopher
Apr 1, 2016
3,435
2,466
Thanks for the thread link. Reading through that answered the questions I had about your advice, especially the bit as to why the 92mm AIO.

So I did try swapping around the orientation of the C14S fan (EDIT: photo was taken before I swapped the fan). So far, it does seem to slow down how quickly the GPU hits max temp, but right now after a 15-20min soak at full utilization, it peaks out at around 78C with 77C being average (still at 1830Mhz). Memory peaks at 98C with 96C average. The CPU is now sitting at 70-72C instead of mid-60s, but I guess that’s a bit more expected since it’s venting air from the GPU now.

I am a bit concerned about the main motherboard power cable now that I’m paying closer attention. It does partially block one of the fans on the FE, although it doesn’t hit the fan at all. And yes, I am aware of the missing PCIe slot cover. I need to go fetch it out of the box.

Good progress so far. Very true that your psu cable is blocking hot air exhaust. Please try to improve airflow..:)
 

Kaiede

Chassis Packer
Original poster
Jul 16, 2019
19
6
Good progress so far. Very true that your psu cable is blocking hot air exhaust. Please try to improve airflow..:)

Yeah, that was my next step, but had to figure out where I put the PSU box that had the original cables for the SF750.

After running the longer original cables, and using some velcro ties to neaten up the cables and keep them out of the way, I did another set of tests. Both with the C14S as intake and exhaust. Did a 20 minute heat soak in both cases. The GPU set for 856mV @ 1860MHz, which is a bit higher than what I had before.

Exhaust:
- CPU: 71C, max 78C (this spun up the C14S fan)
- GPU: 66C, max ~67C.
- GPU Memory: 88C, max 90C.

Intake:
- CPU: 60C, max 67C.
- GPU: 68C, max 69C.
- GPU Memory: 90C, max 92C.

In my case I think running the C14S as intake is a good trade off since the GPU is still staying under 70C at these clock speeds, and only increased 2C while the CPU raised a little over 10C moving the fan to exhaust. I could probably gain some framerate on the GPU if I want, but I’m also sitting at under 250W, saving over 50W from the stock curve, so I’m not in a huge rush to crank it back up from the undervolt/underclock I’ve configured. Especially since I’m able to hold the framerates I want on my 38GL950.

I’ll be honest, I’m a bit surprised that the PSU cable itself was able to block enough airflow to raise GPU temps by over 10 degrees.

Thanks for the pointers and example build, it did help.
 
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MarcParis

Spatial Philosopher
Apr 1, 2016
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Yeah, that was my next step, but had to figure out where I put the PSU box that had the original cables for the SF750.

After running the longer original cables, and using some velcro ties to neaten up the cables and keep them out of the way, I did another set of tests. Both with the C14S as intake and exhaust. Did a 20 minute heat soak in both cases. The GPU set for 856mV @ 1860MHz, which is a bit higher than what I had before.

Intake:
- CPU: 71C, max 78C (this spun up the C14S fan)
- GPU: 66C, max ~67C.
- GPU Memory: 88C, max 90C.

Exhaust:
- CPU: 60C, max 67C.
- GPU: 68C, max 69C.
- GPU Memory: 90C, max 92C.

In my case I think running the C14S as intake is a good trade off since the GPU is still staying under 70C at these clock speeds, and only increased 2C while the CPU raised a little over 10C moving the fan to exhaust. I could probably gain some framerate on the GPU if I want, but I’m also sitting at under 250W, saving over 50W from the stock curve, so I’m not in a huge rush to crank it back up from the undervolt/underclock I’ve configured. Especially since I’m able to hold the framerates I want on my 38GL950.

I’ll be honest, I’m a bit surprised that the PSU cable itself was able to block enough airflow to raise GPU temps by over 10 degrees.

Thanks for the pointers and example build, it did help.
I guess problem is completely solved...:)
Glad to have provided support.

Please keep in mind that Cerberus/Cerberus-X (in aircooling) is providing really good cooling to GPU (almost as good as open test bench)

Now it's time of trial by fire! Enjoy..;)
 

Kaiede

Chassis Packer
Original poster
Jul 16, 2019
19
6
Please keep in mind that Cerberus/Cerberus-X (in aircooling) is providing really good cooling to GPU (almost as good as open test bench)

This is one of the reasons I went with the Cerberus in the first place. But also going to a GPU pulling ~50% more power (at stock) did make me question what the problem was. I’m glad it just needed a little tweaking of cables.

(And I just noticed I got the numbers backwards in the post. I listed the C14S exhaust numbers as intake and vice versa. Whoops. Fixed.)
 
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MarcParis

Spatial Philosopher
Apr 1, 2016
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This is one of the reasons I went with the Cerberus in the first place. But also going to a GPU pulling ~50% more power (at stock) did make me question what the problem was. I’m glad it just needed a little tweaking of cables.

(And I just noticed I got the numbers backwards in the post. I listed the C14S exhaust numbers as intake and vice versa. Whoops. Fixed.)
Yes I noticed inversion of numbers..:)
Hopefully it was a easy tweak..:)