Transfered MoBo to other tower - Won't boot

[pro2a]

I took my old MoBo listed below and moved it to another tower. Everything worked before I changed MoBo's on both towers.

Now on my secondary tower, everything boots up nice, fans come on, HDD spins up but the monitor won't come on. The power button stays yellow. I've reset CMOS, reset the GPU, unplugged peripherals etc... Monitor still won't come on. The monitor is fine. It was just working 10 minutes prior. I did downgrade the CPU on that particular MoBo from a Phenom II to a Athlon 64. I don't know if that will make a difference or not. The RAM is the same. I didn't even remove it from when it was in the old tower.

I'm at a loss here. Any help would be nice. Thanks.

 

[GhOsT1321]

I am guessing that the new CPU is incompatible. Check the mobo manufacturer website on that particular model. If the new CPU is supported, install the old one and flash the BOIS, then install the new one.

 

[pro2a]

I didn't even think of that. I looked and it wasn't compatible. I'm guessing that was the problem. I guess I have to keep the old MoBo in place.