To achieve the best possible performance when installing a Windows system on Proxmox VE, it's recommended to follow the official guidelines outlined here: https://pve.proxmox.com/wiki/Windows_11_guest_best_practices
The key is that in addition to some configuration options, you must first mount a specific driver ISO and load it during the installation process. Finally, install SPICE within the Windows guest to enhance remote performance.
It's worth noting that in newer versions, simply checking the box on the OS page and selecting the specific driver ISO is sufficient(enable Add a additional drive for VirtIO drivers). There's no need to manually add another CD/DVD drive, which is very convenient!
