Apple uses EFI, the future replacement for PC BIOS. EFI does not rely on BIOS settings, in fact, Apple does not have a traditional PC BIOS-style settings options. For setting the time, you do that inside of Windows (or any other OS) just like you would inside of the Mac OS.
EFI hopefully will replace PC BIOS in all future PCs, finally ridding the PC world of 1980s-style computing. Intel has already deployed EFI on their latest laptop line, so the trend is heading towards industry-wide EFI adoption.