Supermicro 4028/4028 with 4090s and cutting the cover?

[Dr. Innovation]

I'm looking at building a server with 4x4090. I had speced things with the founder editions, but the university supplier could not get them and suggested the replacements and I had not checked their length or height. But the ASUS cards, my only option through our supplier, are too tall, even with the bumped-out cover for the servers. (And too long for many of my other servers and other cases). I'm thinking of just cutting out the area in the bumped-up regions (leaving the edges for structural support) so there would be holes above the GPUs while leaving the area over the CPUs to ensure good flow over them and air getting to the edge of the GPU cards. The flow will then hit the GPUs and some will go to the rear of the server, and some will escape upwards, which might actually improve heat dissipation as the outward fans will cause more mixing without the cover. They will all be in a rack with another server above them (6U spacing given the bump was 5u) and if needed I can always add some 1u or 2u fans in the gap if needed to force the air out the back.

Does anyone have experience with such hack jobs? Any problems people can anticipate?
'

 

[Patriot]

Please don't, get 4090 blowers or RTX6000 Adas... don't chop it.

 

[rtech]

Why dont you just shape piece of cardboard to verify it this experiment of yours would work.

 

[Dr. Innovation]

Why don't you just shape a piece of cardboard to verify it? This experiment of yours would work.

excellent idea, though I have enough extra covers (from replacing them in older machines), I was not worried about cutting one that will take a lot more work than a bit of box cutting.

 

[CyklonDX]

I'd say the opposite, as long as you can maintain 1 slot space. Blowers would do just fine. 4x4090 / 4x rtx6000 will do fine in sc 4028 chassis.
If you will run normal high-static pressure fans in sc 4028, you should be fine as long as there's enough airflow. (if you can't get enough space between them with blowers - just remove plastic cover, and fan from the blower cards and it will run just fine in passive.

(blowers work just fine in servers)

 

[Dr. Innovation]

I'd say the opposite, as long as you can maintain 1 slot space. Blowers would do just fine. 4x4090 / 4x rtx6000 will do fine in sc 4028 chassis.
If you will run normal high-static pressure fans in sc 4028, you should be fine as long as there's enough airflow. (if you can't get enough space between them with blowers - just remove plastic cover, and fan from the blower cards and it will run just fine in passive.

(blowers work just fine in servers)

Who makes 4090 blowers? I've searched but did find any. I did just search on alibaba and found some but they said they don't actually have them and tried to offer me something else.

 

[CyklonDX]

In US, only OEMs may have blowers (but you won't see them until end-of-life).
There were some msi blower card (on ebay MSI GeForce RTX 4090 AERO 2SLOT 24G GDDR6X Turbo Graphics Card | eBay -- out of stock)
Quadro cards rtx6000 adas - easiest way to get blower cards or just getting passive Tesla cards.

Most consumer gpu's have pcb that's out-of-standard higher - removing their heatsink won't help to fit in most rac server/workstation cases. (they are design on purpose so they won't fit.)

 

[Patriot]

you have to contact them directly to get blowers... they wont sell retail

 

[CyklonDX]

they won't sell it to him unless in bulk like 200 cards or something.

 

[Dr. Innovation]

Well I though I'd report I got two in there. THe heat sinks are just a bit too high so I'm ording 1U active ones. But just for fun here are pics of it


where I made a foam-board cover. As you can see I have 2 in there and 3 other GPUs so I can better test power demands. No problem with these and GPU-Burn for the 4090's did not exceed 65c (the turbo 3090s got hotter).
Need to get the active coolers for the CPUs before I can layout the 4 GPU version -- these two slots did not intefer with CPU but all others would

 

[mtg]

In US, only OEMs may have blowers (but you won't see them until end-of-life).
There were some msi blower card (on ebay MSI GeForce RTX 4090 AERO 2SLOT 24G GDDR6X Turbo Graphics Card | eBay -- out of stock)
Quadro cards rtx6000 adas - easiest way to get blower cards or just getting passive Tesla cards.

Most consumer gpu's have pcb that's out-of-standard higher - removing their heatsink won't help to fit in most rac server/workstation cases. (they are design on purpose so they won't fit.)
View attachment 32503

Interesting - clever/ evil of Nvidia to spec a non-standard PCB height to limit server compatibility. I wonder if this is enforced via threats or contracts to board partners?

For posterity, the Gigabyte 4090 Windforce V2 (Not V1) are normal height PCBs with rear facing power connectors. The heatsink is massive though, so in a server a waterblock is probably the only option. Byski sells one that is single slot! They did not get any reviews and seem relatively unknown, and are now out of stock everywhere. I wonder if Nvidia asked them to stop?

 

[CyklonDX]

Interesting - clever/ evil of Nvidia to spec a non-standard PCB height to limit server compatibility. I wonder if this is enforced via threats or contracts to board partners?

This isn't nvidia only, it goes to amd too (even worse on amd side of things - you will potentially not find any blower card at all of consumer grade gpu's or with standard pcb/heatsink slot height). As I understand it its made to crypto miners, and servers buy more expensive cards with blower/passive.

For posterity, the Gigabyte 4090 Windforce V2 (Not V1) are normal height PCBs with rear facing power connectors. The heatsink is massive though, so in a server a waterblock is probably the only option. Byski sells one that is single slot! They did not get any reviews and seem relatively unknown, and are now out of stock everywhere. I wonder if Nvidia asked them to stop?

While on some pictures from back - does seem like std slot height, but all pcb pictures i found on that card still shows non-standard height that may be problem in some cases.

(its about 2x of your typical blower card pcb slot height - the picture is making it look smaller than what it is.)

(typical blower std sized card.)

 

[mtg]

This isn't nvidia only, it goes to amd too (even worse on amd side of things - you will potentially not find any blower card at all of consumer grade gpu's or with standard pcb/heatsink slot height). As I understand it its made to crypto miners, and servers buy more expensive cards with blower/passive.



While on some pictures from back - does seem like std slot height, but all pcb pictures i found on that card still shows non-standard height that may be problem in some cases.
View attachment 33518
(its about 2x of your typical blower card pcb slot height - the picture is making it look smaller than what it is.)

(typical blower std sized card.)
View attachment 33519

Interesting - that picture makes it look a little worse than it is? I have 2 of them now, with the byski water blocks. The height looks much closer to the typical blower that the reference picture, not sure how to explain that TBH. I will take a picture of the actual cards tomorrow, but this is the PCB via byski: (Also, the non V2 is a totally different PCB so like, goodluck people who take their advice here...)

According to EE stackexchange, and looking at the backplate dimensions (which cover the PCB), the card is actually within spec: PCIe card dimension half-length 106.68 mm × 175.26 mm specification deviation