Question Suddenly PC won't load past boot screen, keyboard isn't working either

[tfoss1983]

My PC was working fine all day, and then my cat jumped on the tower and hit the power button (usually it's covered because she does this frequently, but somehow the cover got flipped up). I boot it back up and get a Windows 10 troubleshooting page, asking if I want to go into safe mode, reinstall Windows, whatever. I end up uninstalling the most recent update (which was fairly recent) and sending it on its way. But it doesn't boot up. I try restarting, unplugging, etc. Most of the time it brings up the mobo boot screen, but it doesn't respond when I press the keyboard buttons to get into the UEFI setup or boot menu. Sometimes it turns on and is clearly running, but there's no signal to the monitor.

I recently replaced my boot SSD, so I tried swapping the old one back in, but there was no change. Same with unplugging the other drives, so it seems like the problem is somewhere on the motherboard. I replaced the CMOS battery, I switched the jumper to clear the CMOS, and I downloaded a fresh BIOS to a USB stick to try to flash it, but I can't get to the Flash BIOS option since it won't listen to my keyboard.

The mobo is an ASROCK Fatal1ty Killer Z87, and it's several years old at this point, as are the GPU and RAM. The PSU is only 2 years old (it was the source of the last problem I posted here) and I think all of the hard drives are newer than the mobo at this point. I'm not seeing any obvious problems; there's a red LED lit up on the mobo next to the CMOS, but as far as I can tell, that's supposed to be on and it represents that the board is using the primary BIOS, but I'm not entirely sure.

Anyone have any ideas/solutions for me?

Update:
Hardware:
CASE LOGISYS CS369BK R
MB ASROCK|FATAL1TY Z87 KILLER RT
VGA MSI|R7 260 1GD5 OC R7 260 1GD5
CPU INTEL|CORE I5 4570 3.2G 6M R
MEM 4Gx2|GSKILL F3-1600C9D-8GAB R
BD BURN PIONEER | BDR-209DBK RTL
All purchased 2014.
There's another DVDRW drive that I don't know the make or age of anymore.
Boot drive: 1TB WD Blue SATA SSD, about two weeks old, about 120GB used
HDDs: 1 TB WD Blue SATA, used for programs, probably about 1/2 full
2TB WD Blue SATA, used for storage, probably about 2/3 full
2TB WD Black SATA, used for media storage, mostly full (about 50-60 GB open)

OS: Windows 10

PSU: Thermaltake Smart Series 700W SLI / CrossFire Ready Continuous Power ATX12V V2.3 / EPS12V 80 PLUS Certified Active PFC Power Supply Haswell Ready PS-SPD-0700NPCWUS-W, purchased new & installed July 2020

 

[Ralston18]

Starting here:

"(usually it's covered because she does this frequently, but somehow the cover got flipped up).

Not likely a cat problem.

That said, just for the record, are you able to post a couple of photographs of the cover? If so, do so via imgur (www.imgur.com).

Also update your post to include full system hardware specs and OS information.

PSU: make, model, wattage, age (2 years?), condition (original, new, refurbished, used)?

Disk drives: Make, model, capacity, how full?

= = = =

Do you have the User Guide/Manual for your ASROCK Fatal1ty Killer Z87 mobo?

If not go online and find the applicable User Guide/Manual to determine the meaning of the observed red LED(s).

= = = =

Are you able to access BIOS?

Will the system boot via Safe Mode?

If so, as for "obvious problems" look in Reliability History and Event Viewer for any additional related errors.

 

[tfoss1983]

Here's the imgur gallery with relevant pictures:

https://imgur.com/a/ukjQRl5

View: https://imgur.com/a/ukjQRl5


The cover is just a clear plastic ruler I usually have taped over the case's power button. It's not attached now (literally just use some Scotch tape to make a little hinge) because of how I jockeyed the case around trying to disconnect and fix things.

I have the Quick Installation Guide and Software Setup guide that came with the MB, but neither has an explanation of the LEDs. When I searched regarding the red LED on this model board, I ran into a thread (on here, I think) explaining that it was typical, but I'm not entirely convinced.

The system hasn't allowed me to boot into any mode. It does not progress beyond the boot screen. I can't access the BIOS because it won't recognize my keystrokes on the boot screen.

 

[tfoss1983]

Update: So, after sleeping on it, I made the connection that hanging on the boot screen is also what the PC does when I have certain external hard drives plugged into it. While I'd tried booting up with everything internal disconnected, and while I've had those externals disconnected for this process, I hadn't tried booting with all the other USB peripherals unplugged. So I unplugged everything except the keyboard/mouse dongle and the WiFi antenna, and was able to get the computer to boot up. I flashed the BIOS, since I'd been trying to do that anyway, and left it running while I went to work. Everything seems to be working normally, so I'm going to try plugging one USB device in at a time to see what seems to be the issue.

Which leads to this question: does anyone know why having certain USB devices plugged in (mostly external HDDs and USB hubs) would cause the PC to hang on the motherboard boot screen with no keyboard function? I wonder if it has to do with whatever device is plugged into a particular USB port, so I'm going to watch for that, too.