Optiplex G520 Mod

There may not be bios support and or chipset support for that slot. Adding may have no effect or may damage the board beyond repair.

If you wanted to add such a card you should have purchased a system with Power supply and motherboard that supported such an upgrade.

No its not reasonably possible.

i'm still betting that soldering on a connector would make it work.  lacking the skills and time though, I guess we'll just have to leave it at that

Since there is No Selection in the BIOS for AGP vs PCI video what makes you think that "Just a connector" leads to anywhere but damage to the motherboard???

bios support would of course be an issue...    i assumed (haven't checked yet) that there would at least be a way to disable to onboard video so you could add a pci card

I should clarify that we are talking about X16 and not AGP but the principle is the same as far as disable onboard Video. Amazing how personally some people get about that and start flaming away. Still the small layout would take expert soldering skill to not short out between pins.

yes, it would be a pain no doubt, and as I said originally way out of my skill level.

i just found it surprising when i first opened the system up that the pins were already on the board and connected for an x16 slot.