CPU short? Help...

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  • myth77
    Badcaps Veteran
    • Feb 2017
    • 380
    • Croatia

    #1

    CPU short? Help...

    I have asus g750jw, boardview attached...the simptoms were shorting charger...i take it a part...used multimeter on motherboard and almost every part of the board had short to the ground. Using boardview i tried to isolate the problem and finally i found the capacitor on 19v nets...attached capacitor and location..it has short to the ground. Removed it.
    After i removed it i found that some parts/nets of the board have short to the ground and some dont...so, there is a short somewhere else... I removed almost all the joints, couple of resistors...and finally i got short only on +vcore. Not good, i know... Then i removed every last fuc*ing capacitor on vcore but still short...so probobly short on vcore solder joints?
    Can i now safely assume that the cpu is dead? either dead completely or shorted through some bed solder point to the motherboard?
    I am new at this so please any help appreciated...
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  • piernov
    Super Moderator
    • Jan 2016
    • 4435
    • France

    #2
    Re: CPU short? Help...

    Is the short on the upper side MOSFET or on the lower side MOSFET? (ie. between B+ and VCore or between VCore and ground)
    If it's the lower side MOSFET, it's most likely a MOSFET or a capacitor on the VCore line and the CPU is fine (it could be shorted too but that's rare).
    If it's on the upper side MOSFET, one of the MOSFET is shorted and the CPU is probably dead. (the more recent the CPU is, the more sensitive)

    Short on lower side MOSFET: resistance between Vcore and ground lower than 1ohm
    Short on upper side MOSFET: low resistance between B+ and VCore, and a few ohms of resistance between B+ and ground.
    If resistance between B+ and VCore is high and resistance between VCore and ground is of a few ohms, that's a perfeclty normal situation.
    OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

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