4U Case with Threadripper 3970X - Air Cooling Possible?

[jumby]

I was looking for the same info and this was the first search hit. Wasn't sure I could make it work but since I was ok with moving up to a tower case as well, decided to experiment and contribute.

 

TL;DR: Aircooling the 3970x in a 4U case works. Noctua NH-U9 TR4-SP3 cooler with Delta 3.8k fans replacing the Noctua 92mm cooler fans. This plus two Noctua 120mm 3k iPPC case fans cooled the 3970x to 89c during mprime short FFT. Chenbro RM42300-F case.

 

I chose the Chenbro purely for it's short depth. I needed something to fit into my computer cart and didn't want a full depth one. It is not ideal since it has only one 120mm fan cage in the front and the other 5.25" drive cage will need to be converted to a fan cage if you want two 120mm 3ks. There is space for two 80mm exhaust fans and one 80mm intake fan in the front-center SSD cage. Only the single 120mm front intake fan is supplied.

 

Cooling experiments (based on advice in this thread and elsewhere) in case they help someone. All testing with 'mprime short FFT'. Theoretical throttling after CPU hits 95c (Tdir, Tctl in psensor on ubuntu linux)

1. NH-U12S TR4-SP3 with single Noctua 120mm 3k Fan. Builtin case fan, no exhaust fans. Temps hit 95C and cpu throttled.
   1. Too tall for the case by 5mm. Played with the idea of adding plywood shim around the inside of the lid to clear the cooler but decided to test other combos. Did not test cooler with dual fans.
   2. The case has builtin standoffs but I had to use additional mobo standoffs to ensure the IO panel lined up with the back of the case. Without the extra standoffs, I might have been able to put the lid on with the U12S but I would not be able to screw the gfx card in.
2. NH-U9 TR4-SP3. Dual delta 3.8k 92mm fans. Replaced stock 120mm case intake fan with Noctua 3k. Temps hit 95c and CPU throttled
   1. + Removed PCIe slot covers in rear for better air flow: Temps hit 93c.
   2. + Second 120mm 3k intake fan in HD cage. Temps hit 89c. 
   3. I suspect I can cut the HD cage down in length to allow the intake to feed the cpu fans better and maybe bring the temps down ~ 2c. 
3. chrome with multiple tabs, ubuntu graphical desktop, CPU was at 45c (ambient around 72f/22c)

Quite loud at full speed but not like a 1u server. I was comfortable sitting a few feet away from this.

 

Prime short fft is supposed to be a killer. Apparently unlikely to every reach that temp in normal use (my use case is video frame processing in a deep learning application). But even if it does, this setup can handle it. I'll leave it alone here for now.

 

Ubuntu Note: 

• watch -n1 "cat /proc/cpuinfo | grep \"^[c]pu MHz\"" in a terminal to see core freq readouts (-n1 updates the info every 1 second). Credit: (Timothy Martin on https://unix.stackexchange.com/questions/264632/what-is-the-correct-way-to-view-your-cpu-speed-on-linux)
• watch -n1 'sensors' to read cpu temp sensors in terminal updated every 1 sec. I also used psensor gui to graph the temperatures. Sadly could not read the cpu or case fan speeds with my asrock mobo.

 

[WickedGrey]

Sorry for the necro, but this is a very helpful thread (in particular, answers about the 158mm NH-U12S TR4-SP3 not fitting in a 4U chassis).

 

I have a Ryzen 9 5950x in an iStarUSA D-400L-7SE (has 3x 120mm fans between the drives and MB), and the NH-U9S with double fans isn't able to cool the CPU when it's doing single-core boost clocks.  It can handle folding@home no problem, but single core stuff thermal throttles.

 

HTH somebody.