Graphics Card Troubles (HD4870)

[ant_mcbane]

Long story short: Motherboard dies in storm, replace motherboard & CPU, all is merry.
Get more RAM, replace motherboard again due to not supporting RAM.
Suddenly my computer crashes identically to this:
http://www.youtube.com/watch?v=E4CugUm1EuI

I think my power supply is either damaged or underpowered
Would love to hear from you guys!, I'm trying to fix this stupid problem once and for all, it can happen anywhere at any time and the computer will sometimes not POST after it occurs and other strange things, the problem has happened sometimes during booting, other times while browsing the web but most often in games.
Thanks

Edit: Forgot to say...

CPU: Q9450
RAM: Kingston something-or-other DDR2-9600 RAM 4x1GB (At 1066)
GPU: HIS HD4870
Motherboard: Asus P5Q-Pro
PSU: Corsair HX520

 

[Flightsimluke]

Is there any chance you could tell us if you have any:
a) PCI Cards
b) how many hdd's, disk drives
c) fans
d) any other power drawing hardware

 

[rolli59]

Size wise your PSU is fine but it could very well be damaged after the storm.