Multi Quadro GPUs with Mosaic


Here is the context, I have 2 HP ML350 servers with 3 Quadro P4000 per server.
The first one seems to need a Quadro Sync-2 in order to display on 12 fullHD screens (the Mosaic option appears only when the sync 2 card is present).
The second server does not need any Quadro Sync-2 since the Mosaic option is available in the nvidia-settings application out of the box.

The 2 servers are the same in terms of hardware, they are running the same Debian 9 OS, the same Linux kernel and the same nvidia-driver version.

The only difference I see is that the second server is configured in UEFI since the first one is in Legacy Bios Mode.

My question is so : does NVidia mosaic technology suppose to be used on UEFI systems ?
Or it should work as equal on both Bios and UEFI systems ?

Thanks in advance for your help.

IDK, but my guess is rather that often system bioses provide different pci resources depending on boot method (CSM/EFI). You could compare the BAR1 entries of
nvidia-smi --query -d MEMORY

Edit: better said, different resources if CSM en- or disabled. So you could even always have an EFI boot but different resources assigned depending on that option.

Hi Generix,

Thanks a lot for your answer.

There is no big difference in the result of nvidia-smi --query -d MEMORY.
There is a small difference relative to the Total amount of memory on all cards ; I suppose that it is not relevant.

The question is still being opened so.