PC stuck at code A2

subhead · October 11, 2019

PC Specs:

Intel Core i7 8086K (all cores at 5GHz - MCE enabled)

32GB DDR4 Corsair Vengeance RGB (4 x 8GB)

1TB Samsung 960 Pro

Asus ROG Maximus XI Hero

Nvidia Geforce 1080Ti

Corsair RM750

Lian Li PC-O11 Dynamic
Custom Water-cooling loop (GPU and CPU) with Heatkiller V and a Phanteks waterblock

I bought this PC used a few months ago. Had absolutely no problems for a few months. Earlier this week it refused to power on at all. The motherboard lights were on but pressing the power button does nothing (on the board and the case). But it would power on eventually after the room has heated up a bit. I assume it's because of the temperature being too low or something like that. To rule that out, I tried taking out all the RAM, cleaning the pins on them and then reseating them back in, possibly in a different order from when I took them out but I doubt that matters. The PC boots now but was stuck at mobo q-code A2. And I have no display on the monitor.

I did some googling, most of them said it has to do with the mobo not being able to read the drive. The M.2 drive is under a heatsink with a screw. I haven't touched that since I bought the PC, but I'm eventually going to re-seat it when I get the time to work on this in the weekends. Since there's no display I thought I would take the GPU out but I have no idea how to do this without making a mess since it's part of the custom loop. I'm not sure how to go about this. Would appreciate some guidance.

Constantin · October 11, 2019

It smells like a PSU issue to me.....

IkeaGnome · October 11, 2019

Do you have any other drives connected besides the M.2 that has your OS? If you do, and haven't tried it yet, try unplugging the rest of your drives and turning on with just the OS drive plugged in.

I also don't see anywhere that you mention resetting CMOS, give that a shot when you unplug the rest of your drives, but before you power on. Turn system off, unplug from the wall. Pull out CMOS battery(watch battery on Mobo). Hold down your start button on IO for about 30 seconds and let the computer sit for a few minutes with no power to it. Put battery back in, plug the PSU back into the wall then try to start up and get into BIOs. All that resetting the CMOS does is drain all power from the PC so that if it was just a one time issue with a drive not starting right the CMOS will "forget" that it happened. Also, unplugging and plugging the rest of your drives in can help find a bad sata power cable or sata connection to your motherboard.

@subhead

subhead · October 13, 2019

On 10/11/2019 at 6:06 PM, Voluspa said:

Do you have any other drives connected besides the M.2 that has your OS? If you do, and haven't tried it yet, try unplugging the rest of your drives and turning on with just the OS drive plugged in.

I also don't see anywhere that you mention resetting CMOS, give that a shot when you unplug the rest of your drives, but before you power on. Turn system off, unplug from the wall. Pull out CMOS battery(watch battery on Mobo). Hold down your start button on IO for about 30 seconds and let the computer sit for a few minutes with no power to it. Put battery back in, plug the PSU back into the wall then try to start up and get into BIOs. All that resetting the CMOS does is drain all power from the PC so that if it was just a one time issue with a drive not starting right the CMOS will "forget" that it happened. Also, unplugging and plugging the rest of your drives in can help find a bad sata power cable or sata connection to your motherboard.

@subhead

Apologies for the late reply, just got time to work on it today.

I only have one M.2 drive, and it's screwed underneath a heatsink on the mobo. I'll have to get tools to open it up. Couldn't find a screwdriver anywhere here lol.

So I tried that CMOS reset thing, it didn't work. Still showing qcode A2.

Anything else I can try before I decide it's the PSU that's possibly gone?

subhead · October 13, 2019

3 hours ago, subhead said:

Apologies for the late reply, just got time to work on it today.

I only have one M.2 drive, and it's screwed underneath a heatsink on the mobo. I'll have to get tools to open it up. Couldn't find a screwdriver anywhere here lol.

So I tried that CMOS reset thing, it didn't work. Still showing qcode A2.

Anything else I can try before I decide it's the PSU that's possibly gone?

I fixed it. I switched to HDMI from DisplayPort, the my monitor had output. Was able to get into BIOS and make sure all ok. Restarted and all working fine again.

Thanks for the help!