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Peter Mortensen
Peter Mortensen
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Negative DC voltages (-5v5 V and -12v12 V) are rarely used by most modern mobosmotherboards, specifically, -5v5 V which is not present on modern PSUs. The -12v12 V line, although available, is not normally used in the mobo'smotherboard's logic circuitry, but some board designs use this for serial and lan circuitLAN circuits. 

So in my opinion, this is not the main concern and maybe not the main reason for the "dead" mobomotherboard. Since the positive DC voltages of the PSU tested OK, try to test the mobomotherboard with only the CPU and fan and see if the on-board ledLED lit up and the system powers up (use/short out momentarily the power switch connector on the mobomotherboard,just just to eliminate a broken power switch). Before doing this, try to reset/clear CMOS memory first. If the system powers up, connect the other peripherals one by one, in between power ups and hopefully finds the culprit.

Negative DC voltages (-5v and -12v) are rarely used by most modern mobos, specifically, -5v which is not present on modern PSUs. The -12v line, although available, is not normally used in the mobo's logic circuitry, but some board designs use this for serial and lan circuit. So in my opinion, this is not the main concern and maybe not the main reason for the "dead" mobo. Since the positive DC voltages of the PSU tested OK, try to test the mobo with only the CPU and fan and see if the on-board led lit up and the system powers up (use/short out momentarily the power switch connector on the mobo,just to eliminate broken power switch). Before doing this, try to reset/clear CMOS memory first. If the system powers up, connect the other peripherals one by one, in between power ups and hopefully finds the culprit.

Negative DC voltages (-5 V and -12 V) are rarely used by most modern motherboards, specifically, -5 V which is not present on modern PSUs. The -12 V line, although available, is not normally used in the motherboard's logic circuitry, but some board designs use this for serial and LAN circuits. 

So in my opinion, this is not the main concern and maybe not the main reason for the "dead" motherboard. Since the positive DC voltages of the PSU tested OK, try to test the motherboard with only the CPU and fan and see if the on-board LED lit up and the system powers up (use/short out momentarily the power switch connector on the motherboard, just to eliminate a broken power switch). Before doing this, try to reset/clear CMOS memory first. If the system powers up, connect the other peripherals one by one, in between power ups and hopefully finds the culprit.

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miggy
miggy
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Negative DC voltages (-5v and -12v) are rarely used by most modern mobos, specifically, -5v which is not present on modern PSUs. The -12v line, although available, is not normally used in the mobo's logic circuitry, but some board designs use this for serial and lan circuit. So in my opinion, this is not the main concern and maybe not the main reason for the "dead" mobo. Since the positive DC voltages of the PSU tested OK, try to test the mobo with only the CPU and fan and see if the on-board led lit up and the system powers up (use/short out momentarily the power switch connector on the mobo,just to eliminate broken power switch). Before doing this, try to reset/clear CMOS memory first. If the system powers up, connect the other peripherals one by one, in between power ups and hopefully finds the culprit.