Power not reaching the mother board

[chenx]

Hello,
I have a PC motherboard is Mercury PVM900M. it is failing to power on. i have checked power suply it is fine , cpu fan also perfect. first day it started I tried to remove switch cables from the panel and put it back agin and tried to push in the cables hard and the fan rotate after removing fingers from the cables it stopped. Later I switched it on without using the on/off button I removed switch cable from the panel
and it worked .I retauned back the switch cable on the panel and tried to switch it on it refuses it is now two week I have been trying.

Please help what could be the cause? and the way forward

 

[treefrog07]

It sounds like the power button switch has broken. You can replace it with a momentary switch from an electronics supply store. You'll have to solder the leads to the motherboard front panel wires to the new switch, and mount the switch to the front panel.