PC random reboots !HELP PLEASE!

[LamaFish]

Hi, last night, I moved my PC out of my room to quickly clean the dust filter on the bottom of my case to make sure the PSU was able to vent properly, it was a success, but as I plugged it into my room again. it booted, I went to my desktop for about 5 minutes, and went to edit one of my videos for youtube, I opened an .mp3 file. and then the monitor went black. but the fan, LED's and motherboard still had power. the GPU fan was still operating. then it went to shit. it lit back up. then there was a flashing underscore in the top left. it then rebooted as normal, it now continues to reboot whenever it feels it wants to. could it be a PSU issue? also. I did some maths last night and all my components need 5 more watts minimum, the Power supply isnt strong enough to run everything, could this have been damaging the system the whole time? and what can I do to fix it
P.S I still have warranty if it is necessary to replace the whole thing.
THANKS

 

[Dark Lord of Tech]

Make sure the ram is seated properly.

 

[i7Baby]

There's an error somewhere. Its on auto restart after failure.

Boot into SafeMode and disable auto restart on failure. http://windows.microsoft.com/en-au/windows/advanced-startup-options-including-safe-mode#1TC=windows-7

Post your complete and detailed build.

Download HWInfo and run 'Sensors'. Post the results - usually 3 screenshots in TinyPic or similar. This'll tell us how well your PC is running.

Check you didn't knock loose something like the cpu cooler fan lead while you were cleaning out your PC.