Mouse and keyboard stopped working

Hi, today I was makeing an essey in microsof office and suddenly my mouse and keyboard. stopped working, replugging the devices didn't worked (did it for 5 times ) , after this I tried to restart the pc I found out that rr button doesn't do anything , after I stopped the power going to pc and open power + pc they worked for only a few seconds and then stopped again . After a few force shutdown( by stopping the power) the pc closes itself after the windos 8 img dissapear . I have a desktop dual core 3.1, 4gb ram , mouse is usb and the keyboard is with Ps/2 . Any ideas?


Update : after waiting 30 min I reopend it, all worked , but after approximate 3 min pc shuted down by itself.

Sound suspiciously like a power supply issue.

the keyboard its PS/2 and the mouse worked util this morning .

You do not want to unplug or plug in a PS2 keyboard or mouse while the PC is running. The PS2 port is not a hot swap device. Worst case scenario is you could damage the port and make it unusable.
The PC shutting down by itself suggests to me, a power supply issue or an overheating issue.

Nothing new , sorry for posting again , I thought that I ha some new infos but I was wrong .