For those of you that purchased the EVGA half-height 8400GS, here are some resistance/voltage information. This was all done with the pencil mods, resistance/voltage was measured with my Fluke while the card was loaded.
Voltage Resistance
1.25v default 1.55k ohm
1.37v 1.409k ohm
1.48v 1.307k ohm
1.565v 1.247k ohm
1.74v 1.146k ohm

Memory
Voltage Resistance
2.035v default 806 ohm
2.093v 781 ohm
2.201v 744 ohm
2.289v 721 ohm

I'm done testing for the night, got it up to 891/1782/864 with 1.74vcore and 2.289vmem. The core gets up to 47C with my TTBT. The worst part is with the memory at 800MHz, pushing the core from ~750 to 900 doesn't do anything.. hardcore memory limited.