Computer On Its Way Out?

[Cloverjo]

My dad's computer won't switch on properly. It just beeps with nothing on the monitor except saying it's going to sleep. What can I do to help? I am fairly ok with computers, but dad isn't really. I can't think of anything to try.
Any ideas? It's a fairly old PC. Probably is running Windows 7.

[tonyav]

Sure it's not the monitor up the creak, jo.
Worth trying another monitor before you condemn the puter.

[Cloverjo]

Yep, I'd better try that, Tonyav. Thank you.

[Bertrum]

How many beeps if more than one check the beep code this will give you an idea of roughly where the problem lies. A few BIOS beep codes here
https://www.computerhope.com/beep.htm

[Cloverjo]

Thank you, Bertram. I'll ask my dad to listen to the beeps, or listen in myself in a couple of days.

[Cloverjo]

Bertrum, not Bertram, sorry.

[Buenchico]

As Bertrum says, the beep codes might help. A beeping computer can often mean that there's something serious wrong but, equally, it can be something incredibly minor.

Sometimes a key sticking down on a keyboard can be the cause of the problem. (Unplug the keyboard and see if the computer will boot normally).

If the worst comes to the worst though, with the computer being declared dead, the information on the hard drive can probably still be retrieved fairly easily. (You simply need a cheap USB caddy and the instructions for 'taking ownership' of a drive, which we can provide on request).

[Cloverjo]

Thank you, Buenchico. I'll investigate more when I see my dad in a few days.

[CrapAtCryptics]

It may be as simple as something not properly plugged in, check all the connections are firm.

[Cloverjo]

Just a bit of feedback.
Apparently the problem was a memory malfunction and loose bits inside the computer.
Thanks again for all replies.