I have a rather odd problem on one oldish Socket A motherboard . Leave powered off for a day and the power buttons will not switch it back on .
To get a boot i have to jiggle the power lead about until a spark jumps across to the power connection .Sometimes rapid switching on and off of the power circuit mains may do the trick .
Fault is not the PSU nor the case switch nor the power lead nor power supply ( replaced with known good ).Shorting green and black from main PSU mobo connector suffers from the same problem .
I thought that the on power worked on a direct feed PSU mobo connector block to front case connector block thence to power on button .
But this seems like a capacitor or something on the board discharges .
Motherbourd works perfect in all other respects .MSI K7 N2 board .
Any ideas ??

jje