ASUS Z87-Pro V-Edition won't power on after week without power

Ziggidy · February 17, 2020

Hello all!'

I have an issue which arose following a week long vacation during which my PC was powered off with no power supplied to it. The power strip was unplugged while we were gone, and now it just won't power on. It has behaved strangely like this before following total power loss, but usually comes back alive after a few minutes. PSU is fine, Motherboard is the issue. To note, the system WAS properly shutdown before power was pulled. System shutdown, SPU switch flipped, wall plug pulled.

ASUS Z87-Pro (V-Edition)

Intel i5-4590

HyperX Fury 8G stick

I got these 3 as a bundle from Newegg back in July of 2015. It has been basically rock solid up until this weekend when I returned home and tried to power it on to backup vacation photos. System is running a Silverstone DA700 power supply. Initially I suspected that was the issue. Pulled it out, shorted green wire on 24 pin to ground and boom, it powers up without issue. I put it back in the system, no dice. It just doesn't start, no fan spin, no voltage coming out of the PSU. I pulled the GPU, RAM, and CPU, and same thing, the onboard power button on the motherboard lights up, along with some LEDs on the board, but the case power as well as motherboard power button will not power the board on. I know it won't boot in this state, but I would at least expect fan spin and an error code on the LED panel on the board.

Ok, so at this point my only thought is that according to what I have seen from ASUS, this means that the board needs a BIOS update and won't attempt to start until that is completed. I get an 8 Gig USB drive, full format for FAT32 (not quick format), and put the BIOS on it, then rename the BIOS to Z87P.CAP as instructed in the user manual [https://dlcdnets.asus.com/pub/ASUS/mb/LGA1150/Z87-PRO(V_EDITION)/E8335_Z87-PRO_Edition.pdf] on page 3-1. The eject the drive, plug it into the BIOS Flashback port on the motherboard, remove EVERYTHING from the board, all cables and everything except for 24 pin power, and 8 pin power (ESP?), then hold the BIOS Flashback button to update. LED blinks, then goes solid meaning something is borked up.

I tried to run the BIOS updater on a laptop to ensure the file is named properly, but that won't even properly run. At this point I have no more cuss words left and am at a total loss. Any suggestions at all?

Actually, I just thought maybe the CMOS battery is bad. I have a box of brand new ones but can't seem to find it at the moment. While I am looking for that cursing more and replacing it does anyone else have other ideas? CMOS battery I thought just kept the settings within the BIOS and clock during power loss, but not the BIOS itself. Am I just going insane over here?

Ziggidy · February 18, 2020

Ok, so I am now posting this from the computer in question.

This has been the most strange series of events. While looking for a CMOS battery, I decided to clear CMOS settings with the jumper. Now, at this point, the board would NOT start up. The only activity I would get would be trying to update the BIOS with the BIOS flashback button. Other than that, it appeared that the board was fully dead. Anyhow, I move the jumper from normal position to clear CMOS position and it shorts out, I hear a tick then get fans, and the motherboard display is running through codes. Strange. Then I move the pin back to normal position, and everything shuts off and won't turn back on. I try this a few more times and same thing every time. At the clear settings position it tries to boot, at normal it completely shuts down. I am finally able to locate a CMOS battery, replace it, and now it tries to boot as normal. I toss everything back in, it boots to BIOS options where I have to go through boot settings again, then boots into windows with no issues.

At this point, I have learned 2 things. 1st, NO MORE removing this machine from power. shutting down is fine, just leave the juice on. 2nd, time to save up for a Ryzen build apparently.