Thanks for your reply DieHard.
- I've burned three copies of AHT but it's not recognised on boot. I did these both with OSX 10.4 Disk Utility and on Toast 5 under OS9. It still wont boot from the CD even after unplugging all other devices, changing the CD drive to master etc. It's also greyed out in Startup Disk. The Mac OS 9 CD boots every time so I don't think there's an issue with the drive.
- I've cleaned the machine + components as much as possible.
- MB battery is at 2.3V, I often take these out of my older machines since they're always connected to power anyway. How much can this effect things? Unfortunately it's not easy to get another one of these in NZ, I will need to order one online.
- The board is in perfect condition, no damage and no dust.
- I've removed every card other than the video card (I've tried 3 different ones), and have also removed all extra components + cables
- Ports appear to be in good condition
- I don't think this is a thermal issue since it happens when the machine is still cold from a fresh boot
Sleeping works fine in OSX which is why I don't think it's an issue with the machine. It only fails to wake under OS9 and there is no keyboard, mouse, or video response. Just the fans and disk drives spinning up. I've been testing with a fresh install from the image on this site, have tried disabling video drivers, installing newer ATI drivers etc. Have also tried several HDs.
I've reset nvram, pmu, pram which has made no difference. Do you think downgrading the firmware as mentioned earlier in this thread could help?