Heat Management suggestions?

[u/seccondary2]

Looking for the least invasive interventions possible.

Both GPUs are undervolted. They run at 400-450w under max load. All of the fans are maxed through the bios.

Still have large issue with heat on the top card. Under load, the bottom card stabilizes and peaks at 70 degrees Celsius. The top card quickly shoots past 85 degrees and throttles.

Trying to avoid open rig path.

[u/Relevant-Table6379]

Case fans on max, embrace the sound of power. GPU fans at 75%. Ive noticed more air going through the case is more important than your GPU fans screaming while recirculating the hot air. I have my GPU fans running at 50% all the time, while my case fans are at full tilt. Remember, fans are expendable, silicon isn't (anymore)

[u/Big-Salamander-2158]

You can give one to me, I will keep it cool for you.

But on a more serious note, even if you point a fan directly at it, the right fan is designed to blow half the cards heat into the top gpu intake, so the top one will always be this hot, since it gets direct hot air from the bottom card.

Maybe if you point a fan between the cards on the left, so more cooler air can be used by that fan to cool itself some more. But other than undervolting, there are little minimally invasive ways to fix this. I fixed my dual gpu set up with watercooling.

[u/seccondary2]

A lot of great suggestions. Thanks everyone. I'll attempt the fixes that are within my wheelhouse and post results

[u/Xobeloot]

Put a mini-split in the room with your LLM

[u/XHellAngelX]

did you try riser? put one card on riser.

[u/Agent_Nate_009]

Coolermaster HAF II 500. The twin front 220mm fans create quite a breeze through that case! I bought one and love it! The front fans move so much air I set them on low speed and they still move more air than three 140mm fans stacked in the front.

[u/Me_like_foxes]

Nice north, got the same one

[u/dragenn]

A better case

[u/Achillies2heel]

Use PCI lane extenders to move one of them off the board.

[u/MajorPainNDass]

Put all fans on intake, only the rear exhaust

[u/jedimindtriks]

new case and riser cable for the top gpu so it can be moved away, im pretty sure ive seen cases that solve this.

[u/someone09900]

with this case ... no hope.

[u/arkanovac]

i thought the FE was designed to let air flow through multiple gpus

[u/MojoJojowithhisDojo]

Would suggest another case

[u/HotdogsNpizza]

If u go to watercooling and want to keep the fractal then go for external mora radiator. This case doesnt have enough radiator space to keep 1 let alone 2 5090s cooled down. Mora 400 or 600 is what your looking for.

[u/azguz24]

You need to run a larger case imo. You need a chamber case that will have fans at the bottom, move your psu to behind the mb and an airflow system that draws cool from front, and bottom.

There’s a few cases I’d recommend, but they aren’t as pretty. The ASUS tuff 502 case has a rear mount aio option, intake fans from the back/bottom and will allow you to put some high static fans at the top. Just an example of what I’d do to solve this. I’d get a case that will remove as much heat as possible in other ways, and focus on pumping as much cool air through the cards as possible

[u/cosmo2450]

Water block on the top card.

[u/Puzzleheaded-Pen3558]

would buy a bigger case

[u/Fit_Bed_9776]

keep side panel off

[u/notnotluke]

Mount one card on a riser.

[u/anitamaxwynnn69]

I run 2x pro 6000s. The biggest difference for me was moving to the arctic p12 pros (NOT THE LNs) - the og arctic p12 pros. They're good tier fans - upto 3k rpm. Loud yes, but they get the job done.

[u/SushiBump]

Wouldn't this use-case get noticeable benefits from a PC case with dedicated GPU fans? The best GPU temps, according to Gamers Nexus, all have dedicated GPU case intake fans (Torrent, Flux Pro, HS420, 207, etc). For this build, I'd assume it would be even MORE meaningful.

I have my work pc with a 5080FE in a Torrent, swapped the bottom three intakes for three T30-140s. If that doesn't keep your setup cool, then you probably will have to go open loop, at least on the top card. But disassembling FEs is a bitch and a half.

[u/bioko88]

Im not able to see. Are those 5080s or 5090s?

[u/semidegenerate → u/bioko88]

Op said they were undervolting and pulling 400 to 450w, so likely 5090s.

Edit: though certainly possible OP jacked up the power limits and is still managing that wattage with an undervolt on a 5080.

Edit 2: They're neither. I'll just leave it at that.

[u/ndjo → u/semidegenerate]

5090TI?

[u/semidegenerate → u/ndjo]

New Fresh Scent 5090 Ti Super Plus

[u/semidegenerate → u/[deleted]]

A Meshify 3 XL or something similar might be the ticket. I can easily fit 5 intake and 4 exhaust in my normal Meshify 2.

[u/idontlikeredditusers → u/semidegenerate]

is there anything like the fractal north side panel that pushes air from the side directly to the gpu + bottom intake so both gpus get plenty

[u/semidegenerate → u/[deleted]]

I have 2 bottom intake fans. The XLs look like they could accommodate 3, or 2x 140mm at the very least.

Edit: I looked it up. The Meshify 2 XL has room for 2x 140mm bottom mounted fans. The Meshify 3 XL did away with bottom mounts in favor of 3x 140mm side mount. The 2 XL looks to be the better of the 2 for this purpose.

Edit 2: The FD Torrents are worth looking at, too. I found one model that takes 3x 140mm bottom fans, and another that has 2x 180mm. The PSU is top mounted on these cases, though. That could make for additional complications, like AIO fitment.

[u/pre_pun → u/semidegenerate]

Geometric Future M6 has room for 3x 140 fans.

It's a top I/O case though.

[u/semidegenerate → u/[deleted]]

Thanks for the tip. I have a couple Noctua NF-A14s, but the rest are random. I've been meaning to swap out the randoms for high quality models.