Toshiba Satellite C855D-S5307 broken screen, can't get external display

[Guest]

My sister-in-law has given me her (very) broken Satellite C855D-S5307 to try to get some use out of, but it's being difficult...
The screen has suffered a fatal blow, the HDD has problems, and the ZIF connector for the keyboard was unceremoniously ripped from the MOBO. All of this resulting from a tug-of-war battle that ended with a flying laptop. The OEM-installed OS is/was Windows 8 (64 bit).

Before I order a replacement screen, I'd rather verify that the MOBO is OK, but with no display output it's kind of hard. With memory removed, it beeps on POST failure. With memory installed, no beeps. Is there any way to get display output to VGA or HDMI without first having visual access to the UEFI/BIOS GUI?

When I turn it on, the fan sits idly by for a few seconds, spins up for a bit, and within a minute or two it shuts down. I've tried putting a HDD with a working Win7 OS in, but the same thing happens. If I put a Win8.1 install or recovery USB in, the activity light on the usb drive blinks as it's read, so the MOBO must be somewhat functional. As with the original drive, no drive, and the working Win7 HDD, it shuts itself down after a bit of inactivity.

 

[ffg7]

Press FN+F8 to enable external monitor.

 

[Guest]

Press FN+F8 to enable external monitor.

No dice. The keyboard, which can no longer be connected to the MoBo, has the display switch as Fn + F4, but that doesn't work until you're in Windows. I've tried VGA and HDMI, but no dice. I put the SSD from my Win10 workstation in and it remains on indefinitely with that, although it's certainly trapped at a recovery options screen.

I even tried installing the HDD from a working Linux machine. I've had success moving a drive to new hardware and the installed Linux OS just picks up and goes along like nothing happened. Not the case here, though.

I decided that I'm going to order a new display for it, and perhaps work up a case mod to turn it into a tent-style AIO of sorts. At least then one wouldn't be beaten down by the sight of the missing keyboard. And if I get no display with that, then I've got a new display panel to try to resell and a decent battery to scavenge cells from.

Some partitions on the drive are screwed, so Recuva is working on recovering data from the disk now. Once that's done, maybe I can get her files back to her, and recover a license key for a clean install of the OS.

UPDATE:
I decided to return the laptop to my sister-in-law after repairs, as I've got enough computers already. Since it was going back into the hands of her little terrors I went ahead and ordered a new LCD. I was close to scrapping it altogether, but since I was now doing it for someone else, rather than for my own use, eh, why not at least see...
So I got the new screen in from Amazon, and the mobo is ok. I couldn't recover the key from the old HDD so I burned a Win7 key to install Win10. Now that it's on Microsoft's "last" OS I won't have to worry about losing track of the key. Once I have Win10 configured how I want, I'll archive a backup and then she'll be set for the next time the nieces thoroughly destroy it. Once this lappy is done, they'll each have their own and so shouldn't be fighting over them.
We can hope.

There is only a minor issue with the replacement LCD panel, and that is a single dead pixel near the middle of the display. If I run my finger around the area it goes away momentarily. I think this eliminates an electrical fault in the cabling or the MOBO, and leads me to believe there must be a defect in the panel. One dead pixel I can live with. Besides, the little ones aren't going to care a whole helluva lot about one dead pixel.
We can hope

Of note is that there is a setting in BIOS/UEFI for which display to use at boot, with 2 options: LCD-only, and auto. I wasn't sure why no other displays would work on boot with the screen closed or even the LCD disconnected from the MOBO, until... when I got the LCD in, on first boot I was greeted with a BIOS battery low message and prompted to set the clock. Hmmm...

DAMN YOU, BIOS BATTERY!!!
It was probably just jarred loose when the laptop went flying. It also sat in a box quite a while, unused, with the main battery discharged. Still got tons of those coin cells left from when I wore the sysadmin hat my last couple years before retirement.