I bought an HP EliteDesk 800 G1 SFF to use as a virtualization server and router.First I would like to say that if you just want to run Windows, this is a lot of solid hardware for a very reasonable price, jump on it.The one I got has a problem that you should know about. This is enterprise desktop hardware intended for large corporations that want to control their systems and not let the employees monkey with them. And mine came with what HP calls a "stringent" BIOS password. So I was unable to make any changes in the BIOS, including changing the boot order.There are BIOS password reset procedures for this machine online, but they don't work if the password is set to "stringent" mode. HP support site says if you don't have the password, the only thing that can be done is replacing the motherboard.I wanted to install ProxMox on it for virtualization instead of Windows. In order to do this, you have to boot from a cdrom or a USB thumb drive to install it. It insisted on booting the Windows disk, period. I'm an engineer and all, I worked around it by opening up the case and moving the SATA cables around. It turns out that it will boot from the cdrom if and only if there is no bootable hard disk. I replaced the drives and saved the SSD in case I ever wanted to run Windows again. This allowed me to install ProxMox, which is now running just fine.I would still like to get into the BIOS, first because the machine belongs to me and not the megacorp that originally purchased it. Also, I would like to change the CPU fan behavior so it doesn't make any noise until it actually needs to. HP did not make the fan controls and sensors available to the OS so I was not able to control it that way.