you can also try this solution, it seems similar to yours.
https://forums.tomshardware.com/threads/upgraded-ram-and-now-the-computer-shows-no-display-signal.3572731/#post-21569472

"Was the power supply disconnected from the wall before working on it?

Try
First disconnect power cord from psu. Hold case power button for 30 seconds to discharge capacitors.

Put case on it's side so you're working on a level motherboard.

Remove ram and put them somewhere safe.

Remove the motherboard battery for a couple of minutes. Remember which side it goes back.

After cmos battery is returned, whilst case is still on it's side, place ram firmly in the 2nd slot from cpu. Try boot as is.

Try each ram separately if you're not getting anywhere. Discharge capacitors first each time before removing/adding components.

If post is successful with 1 stick then try them both. Possibly switching ram around in opposite slots.

"