I did the solder-your-card Quadro mod, and the hack-your-drivers Quadro mod on my old GTS.
Using either method, net performance gain: zero.
The card behaved exactly as it did before, in every single test I could think to throw at it. And I know I did it right- I had to reinstall my card afterwards, and it was detected as a Quadro by Windows.
IMHO, don't bother with this mod. Lots of risk, and no gain whatsoever. You really don't need hardware accelerated AA lines, etc in today 1.5Ghz+ computers- there's already plenty of horsepower. All the Quadro 'benifits' are in 2D, anyway, if my brain is working.
On the other hand, it was pretty cool turning a $140 card into a $500 card
