My computer is turning on but there is no display or anything?

So, my computer has recently been turning off on its own but when I turn it back on it usually turns on but when I tried turning it back on today when it turned off, the mouse, keyboard, and not even the monitor is working. The fans were running. It just says,"Power Saving Mode" on the screen. There was no 'beep'. It runs on windows 7 and the pc has been used for at least 5 years but recently the UPS got damaged and I haven't bought a new one till now.. So... Can the pc be even fixed now? What should I do to fix it if it is possible to do so?