I’m looking to build my first home server in 2U chassis.
I can’t figure out how to mount GPU (NVIDIA Tesla P40/41), don’t need access to ports.
I have been looking around and could only find SuperMicro MCP-240-21810-0N, not sure if it’s really an option.
I’ve been having hard time figuring out riser cable / card + mounting kit etc. most of the results are for ATX cases.
I feel like you are adding needless complexity in your build. Any particular reason not to use a 4U case? This so that you can use consumer parts and less adaptors /brackets/extenders/etc for the connected things?
What chassis and cpu do you have?
If you don’t already have them, I’d mirror them the sentiment that doing things in n a 4U chassis is generally going to be a much better experience. That way you can just worry about getting a readily available from eBay blower fan bracket to put on the card, rather than the extreme non-compatibility between PCIe card mounts themselves between chassis’s.
Any old 4U chassis with an sas backplane (or a “short” one without drive bays) and an ATX motherboard will give you much more room to get creative, and it’s far easier to cut plasticard and apply painters tape to shape airflow than it is to make a mount for a heavy PCIe card.
For homelabs, 2U systems are only going to save you headaches if you are going to try to connect 1-2 dozen PCIe 4.0 U.2 drives without playing a guessing game of which expensive cables/connectors won’t give you errors if the system is specifically built for it. Otherwise 2U chassis with their custom motherboard and PSU header cabling are going to leave you largely unable to connect and power anything that wasn’t intended.
going to reply to both posts above.
Now that I think about it I should have bought 4U chassis.
I bought 2U chassis (I’ll see if I can still get it replaced, this was quite a some time back) thinking I’m only building NAS (no GPU)
Then while browsing / searching etc I found cheap NVIDIA Tesla on eBay, I bought it.
Finally got motherboard delivered so started building system and realized I can’t fit GPU as is.
Returning it would probably end up being the best solution, but if you can’t, all hope isn’t lost.
If you already have the equipment, then we can still probable figure something out that’s workable enough. Pictures of
-Where the gpu is actually going (does it actually even fit). The GPU doesn’t actually need to be fully secure, so long as you don’t move the chassis too much.
-The PCIe slots you are trying to connect to
-The PSU power distributor, namely what cables or open connections are available
Would be helpful. Also model numbers of everything.
Note that the thing that’s most critical for having the GPU within the chassis is how you are going to power it. Did the chassis come with it’s own dedicated cable to power a GPU? If not, then DO NOT CONNECT the GPU with some random power cable to any available “looks like it fits” 8 pin connector on the PSU header. The pinout of these connectors have absolutely zero standards on the PSU side of things. This mean you can connect the power cable, turn the system on, hear a pop and smell the effects of 12volts permanently and instantly destroying the GPU, and possibly harming the motherboard.
If the chassis didn’t come with a GPU power cable, but has available 8 pin connectors, it’s still possible to use them, but requires using a multimeter on each pin to map out what’s 12v and what’s ground. Then after quadruple checking that the pins on the GPU side of the connector are what they should be it’s fine. If they aren’t, you’ll need tools to remove the pins and possibly to re-crimp pins onto the wires so they are correctly placed. It is exceptionally easy to get things flipped around, so quadruple checking here is not an exaggeration.
Finally, it’s actually not necessary to have the GPU inside the 2U case. For a homelab situation, you can get away with some janky shit.
-For the data connection, you’d want an appropriate x16 PCIe generation redriver card, cables, and finally and adapter to connect the cables to the GPU. Obviously PCIe 4 stuff would work and be more future proof, but it’ll be more costly and I don’t have any offhand recommendations for PCIe 3.0 x16 stuff.
-For power, you’d give it it’s own PSU to power the card and the fans
-For cooling you’d at least need a fitting to attach blowers to force air properly through the card. 40MM fans will be loud, which may or may not be a concern. I generally prefer blower fans if possible. The card might benefit from also having airflow on it’s backplate as well.
-For turning on the external PSU along with the chassis, there’s extending an already available cable outside the chassis, setting up an add2psu on the external PSU (requires 12v and a ground from your main PSU), or using a USB controlled powerstrip (with an adapter to set the external PSU to always on)
The trouble with this is now you’re burning money on additional things, and there may be issues with PCIe hotplugging issues if the GPU is turned off/on when the chassis motherboard or GPU doesn’t expect it. Recent server stuff should theoretically handle hotplugging, but this is iffy.
I myself set up my main chassis to activate the PSU in a old supermicro case I converted into just a straight DAS, though this is a somewhat simpler and much cheaper thing to do than with a GPU since the data connections are just SAS2: Homemade Diskshelf? - #13 by Log
In summary, that’s why we recommend a 4U case. 
Current chassis: Rosewill RSV-Z2850U (doesn’t come with PSU)
Motherboard + CPU: MBDH12SSLNTO and EPYC 7282
PSU: planning to get good PS/2 PSU (got FSP twin, but it’s bit too long so returned that)
GPU: NVIDIA Tesla P40/41, it fits as is
This would work pretty good: Mobestech 3 Vertical GPU Mount Video Card Support Right Angle gpu Holder (can’t include link but it’s on Amazon) but makes setup (holder+GPU) too long, currently looking for something similar but without length
Ah, it’s a barebones chassis, that definitely makes things much easier. I was under the impression you had picked up a preconfigured system, which are usually filled to the brim and only have space/power/connections for what is needed without extra flexibility.
oh no I actually have been building PCs for a while and wanted to try homelab building.
I actually found (on Aliexpress, can’t link):
I can mount using simple PCIe card. However now the next issue is power delivery.
I’ve started new thread to check if there is 180 degrees power adapter.
I’m also looking into buying rosewill-rsv-l4500u
However it will pose the same problem, I won’t be able to connect power to GPU.
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