@sonicj: cycling the mains is not the right word i think. this thing is pretty unstable, sometime i have to off-on 2-3 times, sometime i dont have to. when it cannot ON, i can see a light from transparent plastic of power switch behind, if its turned ON, then i cannot switch ON the PC, i have to switch OFF the mains until the green light is turned off, and then ON the mains again, if it doesnt lit, it will switch ON the PC if i press. if its lit, i have to OFF the mains and redo again.
@joelby: its gigabyte superb 550. power seems ok when its turned ON, i dont see any short of supply so far. i used to buy noname brand before, but that time (3yrs ago), i choosed this gigabyte brand and thought it will be longlasting. its powering Pentium Quad Core Q9400, the dealer said 450W PSU can do iirc, but to be on the safe side, he recommended 550W. if its the gigabyte psu, then the same with no name... designed for the dump.
@alm: yes parts replacement will be time saving... but only if i know what to replace. i never repair a motherboard b4, so maybe i need to do the testing measurement exercise.
@psi: opening the side cover, there are alot electrolyte caps scattered, maybe around 20, they all look ok, no bulge, still shiny, should i test all?
i will gather info here as preparation, in case of full shutdown i cannot ON anymore (meaning i cannot online anymore, from my "framework" at least, i got the wifey netbook for emergency though), i will do full autopsy based on advices here, for now i will let it connected to all my devices (printers, wires etc) until its last blood drop. about the clearing CMOS and reflashing it, any detail info on how to do that? CMOS is the square looking chip inside that we can take out right? i will look for it. but i have no idea on reflashing, is it the same procedure of upgrading the MB firmware?
my suspect will be the momentary switch on the MB, my previous MB that i tossed (to junkyard dept) got the same problem, but the power supply (noname) is still usable.