I've got a 17" iMac G4 800mhz (2002) and took it apart today to replace the hard drive and upgrade the RAM. Here's exactly what I did:
1: Disassemble according to the instructions here: (http://www.ifixit.com/Guide/Installing- ... ent/4176/1
2: Gently vacuumed dust out of the case, trying very hard to not touch any metal components. Did not touch the logic board.
3: Added 60gb SSD (using a SATA to PATA adapter I bought on Newegg)
4: Added 512mb RAM bought from OWC into the non-user-accessible slot
5: Scraped off old thermal paste and applied new paste
6: Reassembled the case
7: Re-inserted the AirPort card and 512mb user-accessible RAM
8: plugged in and powered on
When I did this, the machine made no sounds, neither from the speakers or mechanically. The top fan did not spin up and, to my horror, the computer began emitting a strong ozone odor. I immediately unplugged the machine and let it sit for a few minutes.
I took it apart again and visually inspected the main logic board. I'm not skilled with logic boards or soldering or anything, and didn't notice any blown capacitors or visual damage. I replaced all of the original components that I had replaced and re-applied the thermal paste again, and (against my better judgement) powered it back up. This time I got the chime through the speakers and a brief flash on the screen, but then nothing. Still no fan noise or hdd spin-up. I tried again without the speakers plugged in, and the chime came through the internal speaker sounding like it was underwater. It was working before.
Did I fry the logic board? Is the PSU gone? Can I fix it, or should I start constructing a lamp? Any help would be greatly appreciated!!!