Windows server graphic optimizations

[Oasisnet77]

Hello,
i am facing a strange behavior on customer's proxmox installation.
Recently he migrated windows servers vms from hyper-V on brand new proxmox installations.
these virtual machines are used to run a (rather dated) management program to which users connect via remote desktop. in some management software tables the data input is rather slow with strong lag. Trying to deactivate the table colors and lowering the resolution improves performance significantly. however this did not happen with hyper-V.
The host's hardware features are good with new generation Xeon Silver processors, plenty of available RAM and SSD disks. Even using an additional graphics card on the server does not improve performance. virtIO drivers with 512MB of memory were tested but this also does not help improve performance. Set vm cpu to "host", tested numa configuration and more but nothing helps.
Is there any graphical configuration that can help improve the performance of the VM?

thanks a lot

 

[_gabriel]

graphics are fully emulated in guests.
real gpu can help only if passthrough to the VM.
afaik, same for hyperv.
what about proxmox storage choice ?
for e.g : ZFS can't be compared to NTFS.

 

[helm]

Do not share the primary windows-desktop using VNC or Spice to the host, use RDP to connect to the VM. Clients are Remmina (Linux) or mstsc (Windows).

 

[Oasisnet77]

thanks for you reply.
another test we just tried was to replicate the test on a vm windows server 2019 (in my previous post i forgot to mention that the vm was running windows server 2022). and apparently seems to work out better.
there must be something related to windows server 2022 that does not allow the management software to redesign tables efficiently.