.
(specifically, HP's Pavilion P6-2310)
Excerpted from http://distrowatch.com/weekly.php?issue=20121126#news
Boot machine while pressing F10
Find Secure Boot in the menu tree, ignore warnings
Disable Secure Boot feature
Enable legacy boot options
Enable specific legacy devices, such as USB devices
Save and reboot while holding down F9
If this doesn't work for your device, refer to Jesse Smith's article for clues.
Also, post your solution if some other scheme works for you.
IBM CS821 20-Core 2.827GHz 128Gb 1.92Tb SSD 1U Linux Server - 8005-12N Power 8
$479.96
IBM 8247-22L S822L 2 CPUs 256GB 12x Drives SFF Power8 Linux Server
$749.00
Red Hat Enterprise Linux 5 Server - New and Sealed
$19.99
Asus ESC4000 G3 Barebones 0GB HDD Linux
$200.00
IBM E850 Power8 2x 12C 3.02GHz 512Gb 1.8Tb SAS 10GbE 16Gb Linux Server 8408-E8E
$799.96
1U BareMetal pfsense opnsense Router Firewall DNS Server 6x 10GB Ethernet Ports
$149.00
Dell PowerEdge R730xd Server 2.60Ghz 32-Core 64GB 800GB SSD Debian Linux
$880.25
IBM Power 9 S922 8-Core 3.4-3.9Ghz 128Gb DDR4 2U Linux Server - 9009-22a
$3439.96
POGO Linux WEBWARE 1150 Rack-Mount Server Pentium 4 2.8GHz 512MB - No Drives
$179.99
IBM System X 3250 M5 Single Xeon Quad Core E3-1220 v3 @3.1GHz,8GB RAM,Linux SUSE
$199.87