Hello guys,
i'm tryng to fix this motherboard.
I located and replaced one bad n channel mosfet (short between drain and source and between gate and source) located on the cpu power rail (12 v atx, cpu side ) and two capacitors that were in bad shape. Before the replacement, 12v atx on cpu side was not shorted, bad the mosfet was. The capacitors removed were 4v 680 microfarad. The replacement caps are instead 6,3 v 820 microfarad.
Before the replacement voltage on gate of high and low side mosfet was 0. Now i have 10 v on gate and motherboard can turn on. Vcore (source of high side mosfet or drain of low side mosfet) is now 1.1 with motherboard turned on.
I still can't visualize anything on screen. Psu is working, already tested with another motherboard. I tried to reprogram bios chip but i think the version on msi site isn't correct (it is a file 280, should it be a .bin file?).
Resistance from atx connector listed below seem normal, but -12v is in Megaohm range. 5vsb is 3.75 ohm. Other voltages keep rising beyond 1 kohm.
I posted a photo of replacement and i zipped folder with a schematic and boardview of a similar motherboard (not the same version).
Thanks!
i'm tryng to fix this motherboard.
I located and replaced one bad n channel mosfet (short between drain and source and between gate and source) located on the cpu power rail (12 v atx, cpu side ) and two capacitors that were in bad shape. Before the replacement, 12v atx on cpu side was not shorted, bad the mosfet was. The capacitors removed were 4v 680 microfarad. The replacement caps are instead 6,3 v 820 microfarad.
Before the replacement voltage on gate of high and low side mosfet was 0. Now i have 10 v on gate and motherboard can turn on. Vcore (source of high side mosfet or drain of low side mosfet) is now 1.1 with motherboard turned on.
I still can't visualize anything on screen. Psu is working, already tested with another motherboard. I tried to reprogram bios chip but i think the version on msi site isn't correct (it is a file 280, should it be a .bin file?).
Resistance from atx connector listed below seem normal, but -12v is in Megaohm range. 5vsb is 3.75 ohm. Other voltages keep rising beyond 1 kohm.
I posted a photo of replacement and i zipped folder with a schematic and boardview of a similar motherboard (not the same version).
Thanks!
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