I really, really hate what Gigabyte does with their BIOSes, considering their BIOS backed itself up on the end on some of my disks, changed the OS-visible size of the disk using Host Protected Area (HPA), squashing the mdraid metadata that was happily living there.
By the time I understood what was happening, I had had 3 of my 6 RAID disks screwed, as I had swapped the disks around ignorantly thinking it was some controller error.
That feature was not advertised, and that version of the BIOS had a bug where this feature didn't properly detect which disks it could accomplish this on (it only looked for NTFS/VFAT partitions, natch) and could not be disabled. While I can understand the purpose and usefulness of the feature, releasing with such a bug has made me swear off Gigabyte.
For the reference, it was a GA-P35-DS3, with BIOS F12.