All computer fans spin but monitor says 'no signal'

[ultimatetuber22]

I recently installed a motherboard speaker and all of the sudden it stops working! I don't know what the problem is, I replaced every part but still no results... When I remove all the ram I hear constant beeping indicating that the motherboard is fine. I changed the graphics card for a working one and still nothing, changed the power supply but still nothing! Replaced cmos battery and still nothing.

 

[Husseo19]

well you can't boot without ram. Install one stick and check. make sure all the ram sticks are working as they should. Getting a POST can refer to a ram issue or an overheating issue which i doubt you have.
if nothing works. try to remove the speaker and see if it boots.