Graphics Card

2x VisionTek Radeon HD7970 3GB in CrossFire

AMD Catalyst Driver Version, and Driver History
I've tried 13.2Beta, 13.1, 12.10, and 12.8.

Operating System
Windows 7 Ultimate x64 SP1

Issue Details
No matter which Catalyst Drivers I install they all cause my computer to hang on boot. What happens is WIndows is going through the normal boot process, the 4 spheres float around the screen and form the Microsoft logo, the logo pulses, then just when it's about to load the whole process stops and hangs. I can tell it's about to load because when my computer boots up properly just before the login screen pops up my sound flickers for a second and the LEDs on my keyboard go out then come back.

I know it's the driver because as soon as I go into safe mode and uninstall the drivers (through Device Manager), and run Driver Sweeper until it finds nothing then Windows boots into normal mode with no problem at all. 

What I've tried so far:
Made sure both cards are seated correctly on the motherboard
Express Uninstall from Catalyst Control Panel Uninstaller
Driver Sweeper

AMD Catalyst Uninstall Utility

ATIman

Driver Fusion

Tried, from clean (no hits in driver sweeper), the following drivers:
13.2 Beta
13.1
12.10
12.8

Motherboard or System Make & Model

ASUS P9X79 Deluxe

Power Supply
Antec True Power Quattro 1200W

http://store.antec.com/Product/power_supply-true_power_quattro/tpq-1200/0-761345-27120-2.aspx

Display Device(s) and Connection(s) Used

Dell 2005FPW over DVI @ 1680x1050

Applications and Games
Windows 7 Ultimate x64 SP1

CPU Details
Intel Core i7-3820k Completely Stock 

Motherboard BIOS Version
ASUS BIOS 1103 (Will update to 3305 but don't think there will be much difference)

System Memory Type & Amount
2x4GB Patriot Viper Xtreme Series Division 2 DDR3-1333

 
Additional Hardware
Boot Drive: 128GB Crucial m4 SSD

Storage Drive: 2TB Seagate Barracuda

Number of Case Fans: 3 (+1 from PSU)

No Disk drives or PCI(e) devices besides gfx cards.

Additional Details
Virus Clean: Malwarebytes and SUPER Anti-Spyware both clean.

Do a temp windows install in a temp partition. What happens?

CPU: AMD Phenom II X4 810 @ 3250MHz | RAM: Kingmax 2x2GB DDR2 800 @ 833MHz| MoBo: MSI K9A2 CF v1.0 (BIOS: 1.D)| GPU: Asus HD 6850 1024MB (DirectCu) @ 850/1100MHz | Display: Chili Green Vision L24FHD | PSU: PC Power & Cooling Silencer 750 Quad | OS: MS Windows 95 x64 Edition

CPU: Pentium 4 Northwood S478 @ 3200MHz | RAM: 1,5GB DDR 400| MoBo: Gigabyte GA-8S661FXMP-RZ | GPU: Abit Geforce Ti 4200 | Display: Dimarson 19" CRT | PSU: Noname 400W | OS: MS Windows XP Pro, Fedora 18

Sorry for my English ; ) It's not so good.

After the Windows Logo, you've got a blackscreen?

If this happens, one of your graphic card's may be broken. A year ago, I got the same problem. I changed anything (motherboard, ram etc.). After changing the videocard it worked all fine. 

Try to boot with one card. If it doesnt work, try the other card. Probably you'll find a solution.

Greez, Ore

Right on the money Oreanix. Pulled out the 2nd of the two cards (The one not being used for a display only being used for CrossFire) and the driver installed just fine and Windows started just fine. Talking with VisionTek to get a replacement.