Every time you spin up a virtual machine in Proxmox, the creation wizard makes a stop at the System tab that most people just click straight through. One of the fields there is Machine, and unless you change it manually, it defaults to i440fx, which tells QEMU to build your VM around emulating an Intel chipset from the 90s. Intel’s 440FX chipset launched in 1996 for the Pentium Pro, and there is a much more modern option in the list, so why doesn’t Proxmox use it?