niche' ROMED4ID-2T PCIE Ports usecase

[domrockt]

Hello all together i hope i can get an insight in what iam doing wrong.

I have an ROMED4ID-2T board and an Epyc CPU Rome in it, i have an 1U case and want my GPU to be seated in the "front" since my PCIE Slot7 (Pcie 16x Slot) is occupied by my Mellanox 100Gbe NIC i want to adapt 2 of those SlimSAS (PCIe 4.0 x8) Ports to one PCIe 16x Slot.

AFAIK the Slim Ports 5+6 are linked together by PCIE lanes Pcie G1 0-7, 8-16

so i bought good cables and two of those SlimSAS PCIe gen4 Device Adapter 2* 8i to x16 daughter boards.

so what works and what not, both do 1x8 Mode no problemo but not 16x Mode.

I tried to interchange the cables but no 16x, i tried every bifurcation mode in the Bios.

Maybe i have to change something else? Has anybody tried something similar.

regards Dom

 

[Patriot]

link to what you purchased? I don't know if they support binding those ports together.
You might have more luck if you convert an X16 to SlimSAS via adapter rather than use those ports individually.

 

[domrockt]

link to what you purchased? I don't know if they support binding those ports together.
You might have more luck if you convert an X16 to SlimSAS via adapter rather than use those ports individually.

SlimSAS PCIe gen4 Device Adapter 2* 8i to x16

two SlimSAS 8i inputs one PCIe x16 electrical/mechanical output PCIe gen4 - high quality Amphenol SMT slot, 85Ohm PCB, optimal traces can work in x8 mode with one cable (input near the power plug) can work in x16 mode with both inputs connected (must be the same CPU host port and lane ordering...

c-payne.com

https://de.aliexpress.com/item/1005005606630142.html?spm=a2g0o.order_list.order_list_main.22.1a045c5f1dVxdh&gatewayAdapt=glo2deu

https://www.amazon.de/dp/B0936KFXTP?ref=ppx_yo2ov_dt_b_product_details&th=1

 

[Patriot]

I wonder if it would do better if you used a redriver board from an X16 slot, or shorter cables.

 

[domrockt]

It Works just fine with one cable and 8x, the signal and power is not the Problem, i guessed someone maybe had the same idea. Since my board somehow could bifurcate to 16x i send an Mail to Asrock Support maybe there is an answer Waiting.