You wanted the best, you got... Out of Context Quote of the Week.
"The Mexican rebels aren't running it back for touchdowns, so it's close." (thecubsfan)
Now that I've had time to sit down and deal with the various parts (upgraded the CD-RW to a DVD-RW, added a 60 GB hard drive), I have what could be a very functional PowerMac G4. It appears to be the AGP graphics version, no gigabit Ethernet. HOWEVER, I don't know what else is going on because...
When I try to turn it on, nothing. The power light on the computer will turn on when I hit the switch, then fade out when I let go. I hear something sort of spinning up as well, but it doesn't turn on. It doesn't even get far enough along to do anything else.
It didn't help that the RAM was seated backwards. Technically, not seated, seeing as one end didn't go in. Hmm, could be because of the plastic thingy in the slot that's supposed to go in the notch on the other side. Fixed it, took out the non-matching RAM (if it matters, one stick was PC-100, the other was PC-133)... nothin'. Same issue. The red LED on the logic board turns on when I hit the power switch, as does the case fan, but those go too.
What could be wrong with this? Power supply? Logic board? I snagged this from a thrift store, so I couldn't test it there.
there is a battery on the board that controls the clock and some other things. I can't recall the exact name of it, but I have a G3 laptop that won't boot and it was the part that I think is the culprit.
In your case it should be much easier to try switching the battery.
My first thought would be to check for a stuck key on your keyboard. But if it's happened on multiple computers that's out. Do you use any/some/lots of Firefox extensions? Are any or all of them common to the various computers?