no video signal

I got a Gigabyte Ga-78lmt-Usb3 rev 5.0 motherboard,
msi R9 390 graphics card
windows 7 pro
AMD Phenom II quad core

I got a 2 monitor set up, but don't always run both.
anytime I turned on both monitors the screens go black for 3 seconds, then they both come on as they have since day one
sooo......a month ago
I unplugged one monitor on my dual monitor set up while both monitors were running because the spring of the on and off button broke long ago. I plugged and unplugged the one monitor about 4 times in an hour. each time the screens go black for 3 seconds, then come back on as expected. computer worked fine as usual for several more hours.
I shut down computer for the night and went to bed. The next afternoon I turn on my computer, and there is no video signal.
I reseated all ram.....nothing
I reseated the graphics card....nothing
I installed the old graphics card that originally came with the pc.....nothing
I removed the motherboard battery and held down the power button, then installed a fresh one about 10 minutes later......nothing

this computer has ran flawless since I put it together back in 2015. no blue screens, no flickering. worked perfectly. no sign of power supply failing, no sign of RAM failing......

and ideas on what might be wrong?

phillpower2 said:

The No Signal message means that the screen is ok and that the problem is with the source of the video or the cable that provides the video signal.

Have you tried removing the add on GPU from the PCI-E slot on the MB and hooking the screen up to the appropriate video port on the MB.



Missing from the parts list are the details for the most important component, post the brand and model name or number of the PSU for us if you will.

Can you also let us know how many sticks of RAM you have.

Tip, make sure that you have a keyboard attached and being older hardware if using the USB type make sure that it is connected to a black USB 2.0 type and not the faster blue USB 3.0 type.

Click to expand...

Greetings, thanks for the reply.

I have
EVGA 100-B1-0600-KR (bought it 2016 on amazon it says)

I have 4 ram slots and all are used. 24 gb total (2x8GB, 2x4GB)

I just took the GPU out and plugged into the motherboard. unchanged. "no video signal" This was actually a good idea that I didn't think of trying myself.

originally I was just going to replace things I thought it might be and see if any of those fixed it. that can get pricey though, and I might get stuck with unusable new parts I don't really need.
My plan of attack was reset bios.......replace all 4 sticks of ram....if that didnt work.....replace the PSU....then if that didnt work I might have been cluless and replaced the GPU out of pure frustration.
all these parts seemed to be working flawlessly,but all are old parts that could have failed at any time I'm thinking.

Greetings,
when I push the power button the fans on my GPU, CPU, 2 case fans all come on.
The LED lights on the power button, GPU, case fans all light up.
To shut the computer down I hold the power button until it powers off.

Yes, that is my GPU version.

I did order the BIOS error speaker from amazon today, it should be here within the next couple of days.