Very slow sync on low end PC - what to upgrade?
Probably you are limited by slow hard drive. Even if you're pruning, the hard drive is still accessed. That means you should get a SSD hard drive.
There's a tool on Linux called iostat you can use to see where your computer is spending the most time.
iostat -y 1  # will repeat at 1 second intervals

If your operating system is installed on the non-SSD, then you probably will want to move that also, because operating systems read and write files while they work. For transferring the bitcoin sync progress you basically just need to copy the .bitcoin directory in your home folder, assuming you're on a Linux computer. Probably same for Windows but the directory location is going to be somewhat different.