Isaac at Leadtek has let me know about a new BIOS out for the Leadtek 7800GTX. It increases the core to 450MHz and the RAM to 1.25GHz. This is of course supported overclocking by Leadtek's warranty. He also informed new boards will be shipping with this BIOS.
So what did it do for the card? In a quick 3DMark05 run it scored 8069 compared to the orignal shipping score of 7641. Not too shabby.
The BIOS can be found @ Bjord3D
The BIOS can be found @ Bjord3D