ok, that third image is the sweet spot, that is some sweet BIOS. the onboard is enabled if no PEG, that is good (PEG is old school for PCI. which is the motherboard port that your graphics card is plugged into)
initial display first is set to PCI which is your graphics card.. so if your monitor is plugged into your graphics card, there really should be display.
now, this borrowed dvi cable, it shouldn't be a concern. most monitors have the DVI-D (dvi-Digital only) receptacle (without the 4 pins around the long pin) as well as the VGA. the DVI-I coming out of your 8600 goes both ways, analog and digital. but there is something else..
ok, this is just a hat trick that is harmless, as you can just undo and go back if needed.
your monitor, look at the dvi port in the back of it, does it have the 4 pins around the long pin? if not, then it is digital DVI only. now, if you can get into the internal monitor settings (the buttons on the monitor frame), there will be an option of analog/digital. set it to digital and plug in your DVI cable to it and see if that works. if not, remember that you can set it right back to analog. I am thinking that unless it is getting a vga (analog) plugged into it, it interprets the input as digital and may pick up the DVI input and work.
It is cool that you are helping out your cousin. hopefully it is something you both can learn from. I do it for people all the time. I just hate it when they plead ignorance and walk away while i am performing surgery on their PC. not caring to learn what to do and what not to do and be able to do it themselves if they are on their own.
Edited by synergy513, 17 August 2013 - 04:48 PM.