Graphics Card
2 x HD 5770

AMD Catalyst Driver Version, and Driver History

12.8, happened less often in 12.7

Operating System
Win 7 64-bit SP1 (Aero disabled)

Issue Details
Whenever I play a 3D game and I minimize/close the game (or even a 2D loading screen comes up!), I get a black screen and I'm forced to reboot from the PSU. The odd thing is: as long as I play, no matter how high the gfx is, everything goes fine: no crashes, no freezes, good performances. It just happens when I close the game (both properly and ALT+F4) or minimize it.

Applications and Games
Happened with Battlefield 3, Guild Wars 2, Tropico 4, Company of Heroes.

CPU Details
Intel i7 920 @ 2.67 Ghz, no OC

Motherboard or System Make & Model
ASRock x58 Extreme, Intel Chipset

Motherboard BIOS Version
P1.80

System Memory Type & Amount
6 Gb DDR3

Power Supply
Not sure about this, the label says: OCZ Tech 600 W

Additional Details

Every other driver, directx, OS... Everything is up to date. Doesn't look like a PSU issue, beacuse as long as I play there are no freezes (even with ultra settings). 

What I tried so far:

- Disabling Crossfire and/or Overdrive (if overdrive is on, I just use the default settings)

- Uninstalling/Reinstalling drivers

- Log both CPU and GPU temp while playing (CPU max temp: 70°C - GPU1 max temp: 80°C - GPU2 max temp: 65°C)

It *seems* to me that this is happening way more often with 12.8. When I had 12.7 I disabled Crossfire and BF3 worked fine (had a couple of freezes tho)

Can anyone help me?