I go to turn it on, the fans start up and the computer seems asif it's going to boot for 6 seconds, then for 4 seconds it stops and tries again... It repeats this process over and over. It also makes a clicking noise which i don't know where is from whilst it is trying to boot. I think my PSU might have just broke but i'm really not sure. I haven't added anything to the computer for it to need more power. One thing i WAS thinking was that, i filled up my hard drive, but even when it was full i had turned it off and on and it worked, just 24hours after that... Is the problem likely to be a PSU because i don't want to buy one and not be able a refund? Help me please as i'm really needing my computer back to apply for jobs and other research.