Feedback from PC without USB

Hello,

I'm currently building a monitor rising out of the desk upon starting the Win-PC. Getting a 5V signal from some pin on the mainboard to trigger the stepper motor shouldn't be too difficult, but I would like it to start disappearing into the table when I click on shutdown - not after the PC shuts down and said pin goes LOW. Just looks cooler if the monitor starts descending during shutdown, not after.
Is there a pin I could use that gets shut off right away? Or is there a pin on the mainboard I can turn on and off (with a java executable program in a .bat or something like that)?

Thanks a bunch,
M

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I apologize, I meant more in principle. But yes, here is what I could find that I had in mind.

Unused are

JLPT1
SATA3 (not much longer)
SATA4 (not much longer)
JSPI1
JTBT1
JFP2J
USB1
SYS_FAN3
JLED1
JCOM1

My idea was the sysfan, seemed most likely to be easily turned on and off outside the BIOS. I don't want y'all to do my research for me, but is this possible? Where can I read up on stuff like this?

Thanks,
M

MS7A72V1.0(B250_PC_MATE).PDF (361 KB)

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