Recently, my wife bought a really cheap PC to use at her office. Unfortunately, she wanted Windows XP on it (it came with Linspire 4.5 pre-installed).

Only one problem: the Windows installer would get to the point where it was ready to boot off the hard drive, and fail.

Turns out the hard drive was jumpered "cable select" and the BIOS was set to "CHS." Linux didn't care; I read somewhere that it doesn't look to the BIOS to find out the correct hard drive settings. But Windows did. I had to set the drive jumper for "single drive" and switch the BIOS to "LBA" to get Windows to boot. What a pain.

Score: Linux: 1, Microsoft: 0.