What does the arcadiMac have to do with the QS? confused

http://www.xlr8yourmac.com/systems/quicksilver733_overclock.html

Overclocking is a grab bag. Some machines are great overclockers, others not so much. If you're mildly experienced with soldering and basic electronics skills, there's little risk of doing irreparable damage during the process. Dually noted for destroying a chip with "too much" overclocking. What kills a chip is excessive heat, not clock. Starting the computer without the heatsinks attached properly (or without thermal paste) is a good example.

http://powermac-g4.com/g4quicksilverclockup.html

http://www.macbidouille.com/articles/22/page7

Volt-modding, (not described on any of those links) is a bit more dangerous. However, there's quite a good chance you'd be able to get up to 867mhz on the stock cooler. A simple thermal paste replacement and a higher airflow fan mounted on the CPU HS, and you've got yourself a stable Leopard machine.