Deskop suddenly starts up in BIOS? In need of IT-sage!

[xpluttx]

So i was going to move my deskop.
I turned it off, unplugged everything, gently vacuumed the inside like many times before, moved it, hooked everything back up and powered it on.
Only this time it turned itself off again instantly, then restarted itself and went into this "American megatrends"- BIOS page.
Can anyone please tell me what is going on here, and what steps i need to take to fix it?

 

[Martinr36]

Check all the internal connections, you might have knocked something while cleaning

 

[xpluttx]

So after some research i have found out that when a PC goes straight to the "American megatrends"-page, and it's not showing any special error-messages, then it might be that the CR2032 battery on the motherboard (which is supposed to remember your BIOS settings and such) is out of power. That would make sense in my case as the PC is getting close to 10 years, and it is still running on the original batteries. I am also able to start my PC normally by hitting "save changes and restart" in the BIOS. Since i did no changes it only restarts the computer normally. But now i suppose this will be happening each time i do a restart, so i will try to get hold of some new batteries.