Hey,

I'm just going to post the events leading up to the problem and hopefully you lovely people of the internet can assist me as to where I have gone wrong and possible solutions for me to fix it.

Code:
My PC Spec:
 
CPU:	AMD Phenom II X6 1100T 3.3GHz Black Edit	   
RAM:	Corsair Dominator 16GB DDR3	   
Motherboard:	AMD Crosshair V Formula 990FX DDR3 RoG Series	   
Graphics Card:	AMD RADEON 6870 CROSSFIRE	   
Sound Card:	Creative Sound Blaster X-Fi Titanium Fatal1ty Pro Series	   
Headphones:	Creative Fatal1ty Pro Series Gaming Headset	   
Mouse:	Microsoft Optical Mouse USB	   
Mouse Mat:	RAZER DESTRUCTOR	   
Keyboard:	Logitech Keyboard PS2	   
Monitor:	LG W2363D 23" TRUE 120Hz 3D Widescreen LCD Monitor  
Operating System:	Windows 7 64bit
------------------------------------------------------------------------------------------

1. The PC has worked fine for 6 months, gaming for long periods and no system crashes.

2. I got a new desk set up about 1-3 days ago

3. I decided it would be a good time to install my second graphics card (HD Radeon 6870)

4. I didn't have the crossfire bridge to hand but left the card in the PC anyway to install the bridge at a later date.

5. Booted up PC, worked fine for about 30 minutes

6. Mouse froze, keyboard didn't respond, VGA led light displays as red!

7. Tried to restart, monitor doesn't respond to PC.

8. Red VGA led light is still on

9. Have to turn off PC via the PSU switch.

10. Wait over night.

11. Turn on, boots up fine, freezes 30 minutes in. Same symptoms as #6!

12. Turn off, wait 30 minutes

13. Turn on, BIOS says 'overclock settings failed' (I've never overclocked any of the settings in my life)

14. I decided to just set the overclock settings back to defaults and restart the PC

15. Still freezes anywhere between 10-30 minutes in. Same symptoms as #6!

16. I removed the second graphics card I initially put in

17. Problem still persists. Freezes 30 minutes in, can't move mouse, can't operate keyboard, VGA led light displays as red.

------------------------------------------------------------------------------------------
If any of you can help me out I would really appreciate it, this one has really got me stumped and I don't want to do anything else incase I create further problems.

Thanks in advance,

Hatton