HP DL380e Gen8 - use PCIe slots without using riser board

[seanneko]

My DL380e Gen8 has the rear HDD cage installed which means it's not able to fit the second PCIe riser board. On the motherboard it has a 16x and an 8x slot which the riser board plugs into. I've done some measurements and despite the fact I can't fit the riser board in the case, I can still potentially use the slots on the motherboard with the help of a PCIe extension cable.

I've connected a PCIe to M.2 adapter fitted with an NVMe drive directly to the 16x slot. The server doesn't see the drive at all. It's like it's not there. The adapter and the drive work properly if I put them in a slot on the primary riser board. It's only when connected straight into the motherboard that it doesn't work.

I also tried pulling the primary riser board and connecting the M.2 adapter directly to the motherboard slots for the primary riser. Same problem - card not detected.

Is there a reason why it's not working when plugged directly to the motherboard where the riser goes? I would have thought that the riser simply just converts a vertical slot into a horizontal slot and doesn't do any sort of logic.

This is what I'm doing. Physically it all goes together nicely, it just isn't detected properly.

 

[RolloZ170]

Is there a reason why it's not working when plugged directly to the motherboard where the riser goes? I would have thought that the riser simply just converts a vertical slot into a horizontal slot and doesn't do any sort of logic.

not working. same on supermicro WIO boards. some detection pins(auto bifurcation) and other stuff.

 

[richard.dzavoronok]

Get riser which fits there normally without hdd cage. Take pcb down from that riser. Connect extension from board to riser and second extension from riser to that adapter. You need shorter extension cables though.
It might be working as you are just extending pcie port from board.

 

[Terry Wallace]

No the HP risers have intelligence in them.. that monitors power draw and temps. Without the risers installed the bmc wont enable the slots.

 

[ITGuy327]

No the HP risers have intelligence in them.. that monitors power draw and temps. Without the risers installed the bmc wont enable the slots.

Does it require the cage or just the boards?

 

[RolloZ170]

Does it require the cage or just the boards?

the board and some electrical grounding. can be done with a cable.

 

[ITGuy327]

the board and some electrical grounding. can be done with a cable.

Any chance you could give details. I'm trying to do this in a dl360p gen8. Thank you

 

[RolloZ170]

Any chance you could give details. I'm trying to do this in a dl360p gen8. Thank you

you just expand the Riser from the Board, not the M.2 Card from the Riser.
But at that point you need a 1 to 1 expansion cable because the board slot is not identical to standard PCIe.
The Riser cage connects to chassis ground, that must be done with a cable instead if you remove the cage.

 

[ITGuy327]

you just expand the Riser from the Board, not the M.2 Card from the Riser.
But at that point you need a 1 to 1 expansion cable because the board slot is not identical to standard PCIe.
The Riser cage connects to chassis ground, that must be done with a cable instead if you remove the cage.

So I can install the riser board into the main board where they normally go and then connect those to ground on the chassis or is it a specific location or sensor thank you

 

[RolloZ170]

and you are sure there are no free slots on the first Riser ?

 

[RolloZ170]

i mean the Riser where your SSD now is mounted on, there is a PCI x8 slot on it.

 

[ITGuy327]

and you are sure there are no free slots on the first Riser ?

I'm trying to install a GPU but the card won't fit with the cage. If I leave the cage out then the server won't power on. So essentially I want to trick it into thinking the cage is installed.

Sorry for the confusion. It's a Tesla m2050 that I'm working with

 

[bonox]

they do make a (hard to find admittedly) riser board design to take a double height GPU. It has two 16 lane pcie slots on it. Can you handle an 8 lane pcie connection instead? if so, use an ordinary riser and cut the back out of the slot. Works just fine for me.

You can also cut the card if you want but that's more costly if you go too far.

The riser also provides a power source with an appropriate cable - I made mine from a Gen 7 SAS cage power lead - all the pin outs you need are on the riser at that end and if you buy a $2 gpu power lead, it;s fairly obvious what to connect to what.

Also, my 360 g8 and 380 g8 both fire up without either riser in place. Maybe you've got other things going on. Aside from that, while there isn't that much space to work with, @richard.dzavoronok has the best suggestion if you want it internal. You could even use any old pcie extension with the built-in riser to connect to any GPU in an external box or a gimcrack "leave it lying on top of the case" solution if you want.

 

[ITGuy327]

they do make a (hard to find admittedly) riser board design to take a double height GPU. It has two 16 lane pcie slots on it. Can you handle an 8 lane pcie connection instead? if so, use an ordinary riser and cut the back out of the slot. Works just fine for me.

You can also cut the card if you want but that's more costly if you go too far.

The riser also provides a power source with an appropriate cable - I made mine from a Gen 7 SAS cage power lead - all the pin outs you need are on the riser at that end and if you buy a $2 gpu power lead, it;s fairly obvious what to connect to what.

Also, my 360 g8 and 380 g8 both fire up without either riser in place. Maybe you've got other things going on. Aside from that, while there isn't that much space to work with, @richard.dzavoronok has the best suggestion if you want it internal. You could even use any old pcie extension with the built-in riser to connect to any GPU in an external box or a gimcrack "leave it lying on top of the case" solution if you want.

Without the riser cards in the mb slots or the whole cage?

 

[RolloZ170]

The riser also provides a power source with an appropriate cable

note a PCIe slot not made for GPU can not power 75Watts.
edit:
GPU enablement kit

 

[ITGuy327]

note a PCIe slot not made for GPU can not power 75Watts.
i bet this connector is to power the PCIe slots, not the GPU.

I have 8 + 6 pin power which based on card specs will be good. Just need to get the thing to power on without the cage. Can't find any settings that would disable power without the cage.

Thanks for all the input

 

[bonox]

note a PCIe slot not made for GPU can not power 75Watts.
edit:
GPU enablement kit

sure it can; it's in the specification - mine does above. Also the riser construction is the same between the both the standard and factory GPU riser, meaning that there's no auxilliary power supply that the GPU specific riser card connects to. And the GPU riser card is specced for higher than 75W cards using the auxilliary input provided from the riser card, for which the factory provides this cable (HP GPU POWER CABLE (708915-001)). And this thread was about the gen 8 according to the title; your link is for a gen 9.

There are differences I think in the E and P model GPU riser cards, but neither is needed if you want to cut up a standard card yourself as I did in the picture above.

Without the riser cards in the mb slots or the whole cage?

The cage is irrelevant (it's a mechanical hold device - nothing electrical about it) - you can put the riser card in naked if you want, but you'll need to be careful to stop it breaking off. Mine works without the riser card in either slot of the 380, and without the single card in the 360. Both are P model though, however I doubt that's the defining issue. I might only suggest the latest bios update and looking for options related to the slot that might cause the thing to wait forever for it to appear.

 

[ITGuy327]

sure it can - mine does above. And this thread was about the gen 8 according to the title; your link is for a gen 9.


The cage is irrelevant (it's a mechanical hold device - nothing electrical about it) - you can put the riser card in naked if you want, but you'll need to be careful to stop it breaking off. Mine works without the riser card in either slot of the 380, and without the single card in the 360. Both are P model though, however I doubt that's the defining issue. I might only suggest the latest bios update and looking for options related to the slot that might cause the thing to wait forever for it to appear.

Thank you. I was hoping the metal was not completing a circuit or something.

Appreciate the help

 

[bonox]

Additional - this guy
https://www.reddit.com/r/homelab/comments/j1khb0 mounts the card in the second cage (without the card installed) but runs a pcie extension cable to the primary riser card which might be a better solution for you. You'll need to find a way to support the card though since the pcie extension cable won't be attached to the cage.

Lastly, for what it's worth, try searching hpe documentation for the minimum supported configuration. Usually the documents will say something like "one CPU, one stick of ram, one PSU". I couldn't find mention of the riser in a brief look for power on issues in hpe's doc suite but you might want to go further. If it doesn't mention the riser as being a required component you've definitely got something screwy going on.