Power Mac G4 won't boot

[alfred_bowman]

This Mac has become a real headache. It has 4 memory slots with
256 MB DIMMs in each. It worked correctly for quite a while.
However, last week "About This Mac" showed only 640 MB as follows:

Slot 1 128 MB
Slot 2 Empty
Slot 3 256 MB
Slot 4 256 MB

I shut down correctly and replaced two of those DIMMs. It took
about 10 seconds. When I pressed the power button, the light
didn't go on. The Mac was inoperable, leaving me wondering just
what could go wrong in 10 seconds.

Is there anything I can do? I'm willing to take it to a Macintosh
repair shop.

[nixgeek]

First, try and zap the PRAM. You can do this by holding down Command-Option-P-R when the startup chime sounds. Keep it held down for about 3-4 chimes and then let go. See if this resolves the problem with your RAM.

Your other option is to replace the PRAM battery that might have died. This battery looks like a half-sized AA battery. You can get these at Radio Shack for less than 10 dollars. Disconnect your Power Macintosh G4 from it's power source, open it up, replace the PRAM battery, push the PMU button that's near it (PUSH IT ONLY ONCE!!!!), close up the Mac, reconnect the power, and try turning it on. Some Macs will not work correctly if they don't have a working PRAM battery.

As for the RAM, try swapping the RAM modules into different slots and see if things change. Also, try cleaning out the contacts on the RAM modules with a pencil eraser. Make sure they don't have any eraser debris and put them back in, testing each on in each slot.