"Oh yes, it's very simple!" said the guy on the other end of the phone at OWC. I have a 400 MHz Power Mac G4. I'm running OS X (Panther). I wanted more without having to buy a new computer, so I bought a 1.5 GHz G4 processor upgrade. I was excited! The box arrived, and when I opened it, I thought, "How smart, they even included a screwdriver. This will be a cinch." Wrong. Here's the big catch. What I didn't know is that I would have to upgrade my G4 firmware to version 4.2.8 before installing the new processor, since I owned an AGP Graphics G4 running firmware version 3.something. This is also the case for the Gigabit Ethernet and Digital Audio models of G4. Now, to upgrade your firmware to version 4.2.8, you need to boot in OS 9. And, you need to boot in OS 9 from a local partition, not just the installer CD. I found this out from the Apple support document the OWC manual refers you to (http://docs.info.apple.com/article.html?artnum=120068). Not just any old version of OS 9 will do either, it has to be OS 9.1 or higher. And, to have OS 9 run on a partition, you have to have the OS 9 driver installed on that drive. AAARRRRRGHGHHHHH! So, this meant I needed to wipe my internal drive (both partitions) and re-initialize them with OS 9 drivers. Then, install OS 9.0.4 onto one of my (newly formatted) partitions. Then, upgrade 9.0.4 to 9.1. Thank goddess for having an upgrade disc, rather than having to download it from Apple's website and for those discs not being scratched or otherwise damaged. Now don't think you can cheat by booting from your OS 9 installer or restore CD and just copying the system folder to your drive. No such luck, 'cause, at least for me, I got an unhappy dialog box saying I couldn't do just that, so I had to actually install OS 9. Note that you can reduce install time by installing minimal stuff though. So, I prepared. I backed up all my data. (I highly recommend making disc images using Carbon Copy Cloner, donationware from www.bombich.com.) I made sure my OS 9 and OS X installer CD's were bootable. Then I did the whole wiping, reformatting, installing, wiping again, and restoring. Whew! The actual replacing of the processor was fairly simple. I used the included wrist grounding strap and made sure to reduce any static charge before touching the daughterboard. The only thing I ran into is that the screwdriver OWC provided was just slightly too big for one of the screws. I had to use my own. Plus, the package seal had been opened, and the connector joining the fan had come off, so the posts were bent. Obviously, I got a previously installed or returned processor (not cool). Nonetheless, I moved forward and installed the processor very carefully. After a restart, I checked the "About This Mac" box, and low and behold, I had the green light, "Processor: 1.5 MHz Power PC G4." Yippie! It's been running so smoothly for over a month-no problems. The only thing that aggravates me is that it's louder and spits out some noise around 16-17 kHz. Because it's in my bedroom, I can't sleep peacefully with it on at night. I live in Manhattan, and I can sleep with the traffic on my street no problem, so this must be no minor noise! ($349 direct; www.macsales.com)

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