It depends on the BIOS manufacturer and the OS you're going to run. There are also software solutions which insert translation software into the HD boot sector. See
http://www.tldp.org/HOWTO/Large-Disk-HOWTO-4.html
The restrictions largely affect the boot process. Once the OS has booted, the disk(s) will be handled by the OS drivers rather than the BIOS, so the limit is likely to be set by the controller hardware.