Re: Problems with computer!
First, it's never a good idea to show the world your Product Key, Serial Number, Registration numbers, etc.
As for your issue, it sounds like an intermittent connection. When switches, contacts, pin sockets, etc., age over a period of years, it's not uncommon for the critical contact points to oxidize slightly, causing intermittent connections.
If I were you, I'd unplug the computer. Wait a few minutes for the power supply caps to drain, and then very methodically, one by one, exercise every connection in that machine. By "exercise", I mean remove the electrical connector from your on/off switch, and then slip it back on. Do this 3 or 4 times, and the wiping action as you remove, and reset the connector, will clean the contacts.
Do this with all connectors. Remove, and reset all power supply connectors, etc. There is a good chance when you're all done, you'll turn the computer back on, and will no longer have that problem. You'll never know which connector caused the problem, but it doesn't matter.
If you wanted to know which connection was the actual troublemaker, you'd have to start the computer and try it out after each plug is reset. That's very time consuming, and serves no purpose.
Even if this procedure does not cure the condition, you will have at least eliminated oxidized contacts as the cause, and can move on to troubleshoot in a different way.
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