Greetings folks.
I have one of these Asus Z97 boards that is stuck in a power cycle, with a seemingly irrelevant 00 code - I say irrelevant because the chipset clearly is powering down before its actually able to really figure anything out.
Board is bare, only 24 & 8 pin and cpu in place (both are known good components, 750w psu and I have a number of Haswell cpu's I know are working).
LED's light up when the 24 pin is connected.
When you power it on, it powers down within 1 second and repeats the cycle.
The same occurs with the CPU removed.
Observations:
Caps all appear in good order.
I've been trying but failing to assess any issues in the mosfets - this board has NexFET Power Blocks - the impedance readings from the pins are consistent across all of the chips for the relevant pins.
link: https://cdn.badcaps-static.com/pdfs/...bd749c9daf.pdf
I have what looks like 1.5-1.65V appearing on the output side of the CPU chokes.
I have what seems to be 1.5V on the output side of the RAM chokes.
Both are momentary measurements due to the fast power cycle.
I recall having consistent and high impedance to ground on the CPU chokes. I may not be measuring that correctly though, just one probe on the choke and the other on a USB ground.
If I ask it to reflash its bios - it appears to do that with no issues.
If I remove the EATX 8 pin - the board ceases to power cycle and simply stays on - which leads me to believe there is a dead component somewhere in the VRM - but at this point I just don't know and can't really seem to successfully isolate things - I do know the VRM isn't necessarily the only thing powered by the 8 pin.
Would love it if someone is hiding a schematic somewhere - or if someone has any advice as to the process of how to test these mosfets - or can point me toward other components to potentially isolate as faulty with my little DMM.
Keen to hear thoughts, happy to answer queries.
Regards
I have one of these Asus Z97 boards that is stuck in a power cycle, with a seemingly irrelevant 00 code - I say irrelevant because the chipset clearly is powering down before its actually able to really figure anything out.
Board is bare, only 24 & 8 pin and cpu in place (both are known good components, 750w psu and I have a number of Haswell cpu's I know are working).
LED's light up when the 24 pin is connected.
When you power it on, it powers down within 1 second and repeats the cycle.
The same occurs with the CPU removed.
Observations:
Caps all appear in good order.
I've been trying but failing to assess any issues in the mosfets - this board has NexFET Power Blocks - the impedance readings from the pins are consistent across all of the chips for the relevant pins.
link: https://cdn.badcaps-static.com/pdfs/...bd749c9daf.pdf
I have what looks like 1.5-1.65V appearing on the output side of the CPU chokes.
I have what seems to be 1.5V on the output side of the RAM chokes.
Both are momentary measurements due to the fast power cycle.
I recall having consistent and high impedance to ground on the CPU chokes. I may not be measuring that correctly though, just one probe on the choke and the other on a USB ground.
If I ask it to reflash its bios - it appears to do that with no issues.
If I remove the EATX 8 pin - the board ceases to power cycle and simply stays on - which leads me to believe there is a dead component somewhere in the VRM - but at this point I just don't know and can't really seem to successfully isolate things - I do know the VRM isn't necessarily the only thing powered by the 8 pin.
Would love it if someone is hiding a schematic somewhere - or if someone has any advice as to the process of how to test these mosfets - or can point me toward other components to potentially isolate as faulty with my little DMM.
Keen to hear thoughts, happy to answer queries.
Regards
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