To boot from a GPT partitioned drive you would need an Extensive Firmware Interface-capable motherboard. Disk Unlocker, when run, provides a drop-down list of HDDs with more than 2.2TB capacity (but does not list any that already use the GPT format). When a user makes a selection, the tool creates a new virtual drive that gives the user control over the extra storage space.
"This is the first software solution to overcome current operating system limitations that prevent a hard disk drive from utilizing more than 2048 GB (also known as 2.2TB)," the company said. "With just a few clicks, Disk Unlocker taps into hidden storage space beyond the nominal 2048 GB range, helping you use large hard drives to their maximum potential."