I've removed my old PEXESAT322Is (three of them) and have replaced them with an Avago LSI 9207-8i. The LSI recognizes my drives and seems super fast. Originally, I installed it in my spare PCIe 3.0 slot. Unfortunately, I also pass a GPU through to VMs and it appears that both the LSI and GPU end up in the same IOMMU group. The VMs won't start.

 

I moved the LSI to my one PCIe 2.0 slot (16x) hoping its on another group. Unfortunately, the computer itself won't recognize the LSI card when its plugged into this slot! The LSI BIOS doesn't load and the drives aren't recognized by unRAID (obviously).

 

I assume that even though it's a PCIe 3.0 card, it should work in 2.0 (the manual doesn't indicate anything different--just says it must be at least 8x lanes).

 

Any ideas? I'm really stuck.

 

(Motherboard is MSI Z77A-G45.)

1 minute ago, ksignorini said:

I assume that even though it's a PCIe 3.0 card, it should work in 2.0

Yes, it does.

 

Look for a bios update or some bios settings relating to PCIe, but likely a board compatibility issue.

Just now, johnnie.black said:

Yes, it does.

 

Look for a bios update or some bios settings relating to PCIe, but likely a board compatibility issue.

I've looked through the MB BIOS settings regarding PCIe. Nothing jumps out as having any affect.

Also look for a bios update, not much else you can do.

Just now, johnnie.black said:

Also look for a bios update, not much else you can do.

I'm usually pretty leery to do BIOS updates. You might be right though.

So I did the BIOS update for the motherboard. It's up-to-date now. The firmware in the LSI 9207 is already the most current (checked against their downloads).

 

Still no go.

 

Any other ideas?

Not much else you can do, other than trying a different board.

So I've decided to leave it in the slot with the shared controller w/GPU. I've used something called the ACS Override to get it working.

 

Info on the ACS Override is here: https://forums.unraid.net/topic/42192-trying-to-assign-gpu-to-a-win-10-vm/

4 hours ago, ksignorini said:

I've used something called the ACS Override to get it working.

If you can't get it working on the other slot or replace the board it's a option to try, but keep in mind that ACS Override can have stability issues.

I've done a lot of reading about the ACS Override in the last couple days. The biggest issue is with DMA across devices in the same group--since ACS keeps them from DMAing each other normally. This looks like it's probably only a problem with say, two vid cards in SLI/Crossfire mode, or maybe some similar devices with bad firmware.

 

Even jonp says he uses his GPU and LSI card in this manner (ACS Override on) based on the post above.

 

I'm willing to give it a shot.

1 hour ago, ksignorini said:

I'm willing to give it a shot.

And you should, as long as you know there could be issues, I had some stability problems and I do disable it:

https://forums.unraid.net/topic/37959-guide-passing-through-network-controllers-to-unraid-6-virtual-machines/?do=findComment&comment=602127

 

Gotcha.