Old PC not getting ON

I have an old Intel C2D PC.
Corsair VS450W PSU.
When I try to press the ON switch from cabinet the all fan started to rotate and after just few seconds it stop and become dead silent. Sometimes it even boot and power off automatically. But when it powered on PC running fine without any issue. What could be the reason? PSU ?
P.S. Could not find suitable section to post this issue.

most likely psu issue-check with alternate psu.

I have no extra psu. From today it not booting up and showing no display Either. Black screen on monitor.

take it to a pc repair shop-they will be able to test it.

Revolution said:
I have no extra psu. From today it not booting up and showing no display Either. Black screen on monitor.

Take the cab out wherever it is.
Remove the side panel.
Remove all wires from mobo, remove hard disk or any PCI card or GPU. Remove the mobo battery and short the pins using the batteyr itself for couple of mins.
Reinstern the battery only 24pin, 4/8 Pin wires and hard wire the mobo from front panel pins.
It should beep and boot with minimal hardware support.

If it does, start reinserting eith hard disk at first followed by other peripherals too figure out where does it crashes..

If it doesn't, try another PSU or simply take it to nearby computer market. Easy..

Revolution said:
I have no extra psu. From today it not booting up and showing no display Either. Black screen on monitor.

Clean both ram ( golden contact parts ) and ram slots with 99% IPA. Most probably the motherboard is not functioning anymore or it could be a corrupted bios in which case it may be recovered. If you are planning on using this setup then there's cheap motherboard ( from brands like asrock, biostar etc. ) available in Chadni Chowk, kolkata around 1200 -1400. You are from Kolkata, right ?

i have a zebronics g41 mobo lying around and was thinking of selling it off.

topgear said:
Clean both ram ( golden contact parts ) and ram slots with 99% IPA. Most probably the motherboard is not functioning anymore or it could be a corrupted bios in which case it may be recovered. If you are planning on using this setup then there's cheap motherboard ( from brands like asrock, biostar etc. ) available in Chadni Chowk, kolkata around 1200 -1400. You are from Kolkata, right ?

Yes I'm from Kolkata.