+1 here on a ProLiant DL580 Gen8 with latest available firmwares / ilo (beside this is disable the the embedded serial prt - only use the virtual serial port).
Tried Virtual USB Images and CD/DVD by Browser and Remote URL over a Apache on the same LAN - with different Linux distribution medias / install media (ans different boot loaders like grub2, isolinux, syslinux). For me that seems a bug within the BIOS / iLO firmware from HP, especially while boot loaders. If using the "One Time BIOS Boot Menu" it goes a bit further crazy - it just seem to "hang within" that boot menu.
This taked me several hours to fiddle that out - while each pre-boot / hardware check (seems the "shortest" version) takes >5min on that machine. Just wondering, why this is still an issue - Linux is not an "exotics" on such machines...ß)