1. Update your computer's firmware. If your computer is a Power Mac G4 (AGP Graphics), Power Mac G4 (Gigabit Ethernet) or Power Mac G4 (Digital Audio) machine, you must make sure the firmware is up to date at v4.2.8. With the processor upgrade card installed, outdated firmware can prevent the computer from booting up, or cause instability during operation. QuickSilver models already have up-to-date firmware, and should not be affected by this issue.

2. Reinstall Mac OS 9. Do the problems occur only when the system is booted in OS 9? If so, and the problems don't occur in OS X, how was the OS installed? It's possible to use installation CDs from a later machine to install OS 9 to an earlier machine. Doing so may result in the wrong ROM file being installed on the older computer; this will cause instability with the new G4 chip. If this is the case, you should reinstall Mac OS 9 from either the system's original CDs, or from a retail version of Mac OS 9, and then update the OS to 9.2.2. For more info on updating the ROM file go here.

3. Update the firmware of any PCI adapter card installed in your system. Certain older PCI video cards (for a second monitor perhaps) may have outdated firmware on them that is incompatible with the new G4 chip. SCSI cards with outdated firmware and/or software are also likely candidates. To resolve the issue, you should reinstall the original processor, download any software necessary to update the PCI card's firmware, update the firmware, and then install the Encore/ST card again.

4. If a software disk was supplied with the processor, please make sure you've run the istaller program. For Sonnet and OWC Mercury Extreme processors: Simply open and run the program provided on disk. For PowerLogix processors: perform the following steps with the *original* processor installed.

• Make sure that you have the latest Apple firmware for your computer. You can find the latest version of the firmware and installation instructions here .
• Once you have updated to the latest Apple firmware, put the Powerlogix CD in the drive, then shut down your computer and let it set for approximately 10 seconds.
• Hold in the Programmer's button (the indented one) on the front of the computer, and push the power button. You should get a long tone. Immediately as the tone ends, release the programmer's button and hold down the "C" key on your keyboard. If you performed the step correctly, you should boot to the Powerlogix firmware updater - Black text on a bluish background. If not, try it again.
• Select the option to install all updates. If you have the latest firmware, and you held down the programmer's switch properly, the firmware should install. If not, you will need to repeat the previous steps.
• Once you have updated the firmware, select the option to shut down.
Once the computer shuts down, you may then install your Powerlogix processor.