Power Macintosh G4 MDD (2003)

My unit is in good condition except one hard drive chassis which is missing. Because you can put more 3.5" HDDs there, I just used another bay and longer cable to ATA100 port. It can run Mac OS X 10.5 without bigger performance problems.

WARNING!
If you plan to re-install a primary hard drive, make sure that you're using an ATA-100 port! Using drive in ATA66 port makes drive slower, and the Mac, expecially with small RAM installed, becomes very slow. The ATA-100 port is located on the edge of mainboard near case hinges, it's easy to find it as it's mounted that the plug goes in parallel to the mainboard.

If you have any stability problems, check the RAM first. It should be put starting from the first socket (bank), look at the mainboard for its marks. Putting modules from the last socket leaving first ones empty gives many problems with stability.

Here you'll find:

Overclocking

As they're overclocking quite easy, it still requires some soldering skills, so you're overclocking it for your own responsibility. Don't blame me if it won't run!
My unit is overclocked to 1.66GHz and works well, unfortunately I don't remember the voltage - probably 1.6V.  It works well with 10.5, as I put 2GB of RAM in it. With 1.5 and 1.6 (512+512+512+128) it still works good.

To overclock this computer, you should remove CPU module from mainboard. The best thing now is to decide which frequency you want to get and write down settings needed. Here's the picture where to look for resistors (drawings show default settings):
 

PLL resistors are for CPU multiplier. Resistors are 0-ohm value, so you can just connect pads instead of soldering resistors to them. In this table 0 means pads are connected (resistor installed), 1 - disconnected! (pads connect pin to ground).

Now the voltage. Flip the board and locate VID resistors. Their config is (0 - resistor in place):

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