Try resetting the PRAM.

Are you booting to Disk or HD? Version of OS?

Might be if you're using a non-oem OS (You don't say what size 1.5GHz or any other details (post a SN#)) that you need a firmware update to use your OS.

Do you have your Hardware test disk? Can you boot from that? (might be a good place to start)

[quote|machead3]Try resetting the PRAM. Are you booting to Disk or HD? Version of OS? Might be if you're using a non-oem OS (You don't say what size 1.5GHz or any other details (post a SN#)) that you need a firmware update to use your OS. Do you have your Hardware test disk? Can you boot from that? (might be a good place to start)[/quote]

Hi, the exact thing happened to me with my PowerBook G4.

I had to reset the power manager. Read this site, and see if it helps you.

http://support.apple.com/kb/HT1431

Peg

[quote|aturnaround]Hi, the exact thing happened to me with my PowerBook G4. I had to reset the power manager. Read this site, and see if it helps you. http://support.apple.com/kb/HT1431 Peg[/quote]

I have a question for you. When you put everything back together and reset the power manager, and it works... let me know if that did it for you. Plus, let me know if you experience any static like lines across your screen. That happened to me and that I still cannot figure out.

Thanks,Peg

[quote|aturnaround]I have a question for you. When you put everything back together and reset the power manager, and it works... let me know if that did it for you. Plus, let me know if you experience any static like lines across your screen. That happened to me and that I still cannot figure out. Thanks,Peg[/quote]

Thanks for responses. Model is A1095. I've been trying to boot form HD and then from install disk (1 of 2). Same symptoms persist even after PRAM reset. Fan and disk sound like they're getting up to speed, then chime begins and cuts out. Screen remains blank throughout.

One cncern is that I haven't applied thermal past correctly and that I used it where there was the remains of a thermal pad. One clue to this is that after my various attempts to reboot the underside of the Mac at the keyboard - around the processor - are very hot. I've never used a G4 PowerBook before, but this seemed excessive.

Cheers

GSJ

[quote|gsj4gsj]Thanks for responses. Model is A1095. I've been trying to boot form HD and then from install disk (1 of 2). Same symptoms persist even after PRAM reset. Fan and disk sound like they're getting up to speed, then chime begins and cuts out. Screen remains blank throughout. One cncern is that I haven't applied thermal past correctly and that I used it where there was the remains of a thermal pad. One clue to this is that after my various attempts to reboot the underside of the Mac at the keyboard - around the processor - are very hot. I've never used a G4 PowerBook before, but this seemed excessive. Cheers GSJ[/quote]

you may be losing full contact on somthing like the GPU of CPU, kinda like what causes the RROD on xboxes, but try re-applying the thermal paste, and than letting it sit and heat up for 15 minutes or so, rebonding the solder connection on the Bad connection, this ususally only works temporarily though

[quote|Chris Green]you may be losing full contact on somthing like the GPU of CPU, kinda like what causes the RROD on xboxes, but try re-applying the thermal paste, and than letting it sit and heat up for 15 minutes or so, rebonding the solder connection on the Bad connection, this ususally only works temporarily though[/quote]