Hello!
I posted about this same PC a few days ago, but after testing it without the GPU I've found something odd. When I try to boot to the BIOS with a GPU plugged into the monitor, I get so signal. However, when I try it with the motherboard's graphics, I'm able to get into the BIOS just fine. I tried this with two GPUs (HD 6850 and an HD 7870) with the same result. It's also worth noteing that whenever the PC is turned on the CPU fan goes to 100% without fail now. Any ideas?
Specs:
Core2Duo E8500
4GB Kingston DDR2
Gigabyte GA-945GCM-S2C (Motherboard)
Saphire HD 7870 Ghz Editon
Toshiba 250GB 2.5 inch HDD
Seasonic SSP-450RT PSU
CoolerMaster N200
Thank you!
Edit: And yes, the display cables are plugged in correctly, in case you were thinking that.