Computer freezes and can result in a BSOD

Hey, recently I have been having a recurring issue much similair to this event ID 41 Kernel Power issue which seems to restart everyones computer. However I have one slight difference. I usually end up with a frozen display. This could occur randomly much similair to the above problem but seems to be mainly when I do something, click a button, Push-to-Talk using VOIP software or even open the start menu. This problem has been very persistent over the past 2 or 3 weeks now with no indication of starting. TO be honest I had a crash much similair to this after 1 month of owning the computer but then it never occured again, til now. The computer is relatively new so I assume it shouldn't be outdated software. I have tried driver updates, memtest and many other things (again similair to the above problem :P) but to no avail. I have not done a clean format with windows 7 reinstalled yet as I do not have anything to transfer all my files on to and chances are I wont get an external for at least a week from now. So in the meantime I've been trying to beg for any fixes to this. So lets pretend I have nothing and go through every single step of things to do to try and fix this.... Though we can exclude anti virus scan as I shall leave it doing that now. Any help would be more than loved.

System Specs

• AMD Phenom II x2 550 Black Edition 3.1GHz 7mb cache
• Gigabyte GA-MA790FXTA-UD5
• 4gb DDR3 PC8500
• 2 x ATI Radeon 5600 HD
• 500gb Western Digital HDD 32mb cache
• 22x DVDRW
• Antec 900 EU Gamer case
• 850W PSU
• Windows 7 Home Premium 64 bit