I've got a 13" mid-2012 MBP running OS X 10.10.3 Yosemite. I've recently repaved it with a fresh install and now I'm getting round to Bootcamp`ing it. I've installed Windows 8.1 in EFI boot mode and discovered the well documented issue with the sound card not working. Following various online guides to install Windows in legacy boot mode, I've held option at boot and selected "Windows" on the USB thumb drive that Bootcamp Assistant created but all I get is a black screen with a white blinking cursor. I've left it for 10 minutes but still nothing (some reports say it boots to the installer after a while).
I believe the disk is hybrid MBR (due to Bootcamp Assistant), here's the output from fdisk
Gregs-MBP:~ greg$ sudo fdisk /dev/disk0
Password:
Disk: /dev/disk0 geometry: 60801/255/63 [976773168 sectors] Signature: 0xAA55 Starting Ending #: id cyl hd sec - cyl hd sec [ start - size]
------------------------------------------------------------------------
1: EE 1023 254 63 - 1023 254 63 [ 1 - 409639] <Unknown ID>
2: AF 1023 254 63 - 1023 254 63 [ 409640 - 486812704] HFS+
3: AB 1023 254 63 - 1023 254 63 [ 487222344 - 1269536] Darwin Boot
4: 0B 1023 254 63 - 1023 254 63 [ 488493056 - 488280064] Win95 FAT-32
How can I get Windows to install in legacy boot mode?
Note, I previously had Windows 8.1 working fine (audio and everything) and if I remember correctly I just ran Bootcamp Assistant and followed the instruction, no trouble.