Hi my PC has recently started just turning off either when booting up or when running at random.
Is this a power supply problem????
No blue screen or anything just switches straight of.....
Opened it up to look and checked all connections and now I get the following message when starting....
"one of the files containing the system REGISTRY data had to be recovered by use of a log a log or alternate copy. The recovery was succesfull"

I dont think this is related to the powering off as it powered off before I started getting this message

It could be a power supply problem. That is probably what I would check first, either by swapping in a known good one, or having that one professionally tested.

This could also be caused by heat - make sure interior is free of heat-trapping dust and all fans are spinning. Other causes could be failing RAM or failing motherboard.