Hardware tweaking is not possible.Might work thing is BIOS flashing.But at least have to get BIOS from an exact physically looking(except cooler and colours) VGA.
But then chances are like 1~5% and u will need a PCI VGA to reflash the BIOS to original if our flash doesnt work out.VGA is safe nevertheless.And to remind nVIDIA BIOS flash is a pain in the ass looking at ATI Win Flash