Computer build won't work

[brcamphouse]

So I starting on a computer build for my friend. I'm not exactly new to computers yet this issue has me absolutely stumped. He got ahold of an old motherboard and an AMD a10 5800k, a 600 watt corsair PSU and a GTX 750 ti. We put the whole thing together and all the fans turned on and all the lights lit up but there was no signal to the monitor. The keyboard also didn't work, though there was a flash of power that went to it that made it light up. The beepcode was a constant beeping that didn't stop no matter how long we left it. I figured it was the motherboard so I switched the old motherboard out for a new one. When we hooked up the new one, the blue decorative light on the front of the computer had a red light lit up along with the blue that flashed slowly. The CPU fan slowed down and struggled to spin, changing its speed in an unhealthy, pulsing way. I unplugged the CPU power and it ran normally, and the red light in front stopped. I hooked up an old power supply and the light was gone and the CPU fan worked right but there was still no signal to the monitor. I'm not sure what the problem is or what part needs to be replaced.

 

[Atomicdonut17]

Are you using some sort of adapter to relay the signal between the 750Ti and the monitor? Ex: A VGA to HDMI/DVI adapter? That might explain the display issue, at least. As well, for the motherboard, I suspect that it was just old and faulty, the specifics are lost to me, someone else more professed might be able to satisfy you on that. I had a similar issue (minus swapping out the board and the flickering) where I tried to use a VGA to HDMI adapter that wouldn't work because the 10 series of GPUs doesn't support Analog anymore. however, that might differ with the 750ti, because it's older..

After I removed the GPU, and used my motherboard IO, I got it to work. I had to later come up with a more intuitive solution than just not using my GPU, so I used a HDMI to DVI-D cable (because my monitor was old and only had VGA/DVI) and it worked.

 

[russrn16]

This happend to my friends build with same specs. Turns out the motherboard was faulty. Try replacing or using warranty.