just thought I'd share a little experiment, maybe it'll help a few of you trying to do the same thing...
I installed a 800MHZ QS single-processor and Heatsink in my 466MHZ DA, this was made possible through the 12v feed on the 4th mount.
The feed came from the yellow wire of a free hard drive connector, which I clamped in a 16-14AWG (8-10 stud) ring terminal, I then attached the terminal with an 8x32 - 3/8 screw with matching bolt, sticking a couple of #8 internal lock washers in between, (screw head upside down to preven contact w/ the MB), on to the 4th mount of the QS module. The three other mounts act as grounds, so no need for a ground wire... So, NO NEED TO SOLDER ANYTHING.
The good thing was I didn't have to adjust the fit od the HS in the case, because it fits just right, so overall it was pretty easy, but I have to admit I had the shakes when I booted up!!!
Here are a few bench tests comparisons using XBench:
CPU Test 45.66 85.40
Quartz Graphics 76.09 88.58
Open GL 51.99 69.52
This is with 1.28G of Ram, and an ATI Radeon 8500 with 64M of DDR ram
The machine is not any louder, and I can leave my hand on the heatsink for a while right after I'd been using the machine intensively... so no overheating problems...
There you have it people, I'm a happy camper now...