Testing +5VSB on PSU to check whether PSU is defective
I am having comp troubles and with my limited resources here I try to troubleshoot whether the problem is PSU or motherboard related.
(Eg. mainboard doesn't start up right now)
I have a ca. 6 year old "Thermaltake Toughpower 750W"
When i jumper (paperclip "trick") the PSU PS_ON/GND (unplugged from board) then I can measure the rails, +3, +13, +15 etc. seem all be fine. PSU is also starting, fans spinning etc.
I even can put a 5V bulb on the +5V line and its lighting up.
Now to the +5VSB line (purple wire):
When I do this "bulb test" on the +5VSB line, the light does NOT light up. I am getting the same problem as if i would plug in the PSU to the mobo, board is not powering up etc. and I can hear a very soft 50hz "ticking" inside the PSU.
If i put the 5V bulb to the normal +5 rail on the PSU and it lights up, but does NOT on the +5VSB rail, can I assume that the problem is with the PSU?
(Mind you that measuring the +5VSB rail with DMM otherwise tells me everything is allright, I measure 5V something on the DMM, however as mentioned I cannot drive the bulb from that voltage)
If Nvidia logic applies we can buy $400 graphics cards for $350 plus $50 in Monopoly money.