FYI, I recently bought an HP Pavilion desktop off the shelf at Walmart and `OpenBSD 6.3 GENERIC.MP#11 amd64' installed no problem from the `install63.iso' image burned to DVD. Intel Core i3-7100 processor 8GB SDRAM 1TB hard drive
You will need to disable UEFI Secure Boot and enable Legacy Support : https://support.hp.com/us-en/document/c04784866Then specify the DVD as the boot source: https://support.hp.com/us-en/document/c03659945
