Try unplugging the machine or even both of them if you can from the power cable and even the monitors as well. Click the power button while unplugged a few times on the computer and monitor to clean out the power.
Alcohol will just make it go to sleep and we don’t want that lol
Any capacitors you can see that went bad?
I would leave it out for awhile and really let it drain for awhile and try to again. If you are adept in trying you can take it apart and really take a look at it.
If not sometimes a card or part will continue to work but once removed or powered down they stop
I don’t see it on the picture, but does it have a BIOS switch? Any chance you disturbed it? If not, you could try hot air station to reflow. Use a lot of flux. There is a chance that while manipulating the card in the PCIE sockets you bent it slightly and old solder cracked somewhere.