How can I move my system from CSM to UEFI (Also, does AMD SAM work in a Windows VM)?


Oct 15, 2021
Hi, I installed my system on legacy bios and want to convert it to UEFI. The reason is that I want to use Smart Access Memory in a Windows VM ( I heard that it works but I didn't find much about it sadly).

This is my configuration if it helps, the system is installed on the 2 nvme drives using lvm. I used the official Iso to install proxmox. My version is 8.0.4 upgraded from 7.

sda            8:0    0 931.5G  0 disk
└─sda1         8:1    0 931.5G  0 part
sdb            8:16   0 465.8G  0 disk
└─sdb1         8:17   0 465.8G  0 part
sdc            8:32   0 232.9G  0 disk
├─sdc1         8:33   0   100M  0 part
├─sdc2         8:34   0    16M  0 part
├─sdc3         8:35   0 232.2G  0 part
└─sdc4         8:36   0   591M  0 part
sdd            8:48   1  29.7G  0 disk
├─sdd1         8:49   1   224K  0 part
├─sdd2         8:50   1   2.8M  0 part
├─sdd3         8:51   1     1G  0 part
└─sdd4         8:52   1   300K  0 part
nvme1n1      259:0    0 476.9G  0 disk
├─nvme1n1p1  259:1    0   512M  0 part /boot/efi
└─nvme1n1p3  259:2    0 476.4G  0 part
  ├─pve-swap 253:0    0     8G  0 lvm  [SWAP]
  └─pve-root 253:1    0   1.4T  0 lvm  /
nvme0n1      259:3    0 931.5G  0 disk
├─nvme0n1p1  259:4    0 696.1G  0 part
│ └─pve-root 253:1    0   1.4T  0 lvm  /
└─nvme0n1p4  259:5    0 235.4G  0 part
  └─pve-root 253:1    0   1.4T  0 lvm  /

So is converting it to UEFI possible and low risk? I don't want to reformat my whole system. And does SAM even work, to begin with?
Thank you!
AFAIK, Resizable BAR (SAM, CAM) does not work with QEMU and PCI(e) passthrough (yet) and you need to disable it in the motherboard BIOS. Let me know when I'm wrong.
I am not sure, to be honest, I saw posts where people got it running and some that said they couldn't.


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