You didn't mention either replacement of the 3.6-V lithium half-AA PRAM battery or starting up with one of the four-fingered salutes. If the battery was already of pensionable status when the Classic went into a cupboard, it is beyond that now. Better no battery than an exhausted battery, and best a new one.
Do you hear or feel the HDD spin up? If it doesn't, you'll need an alternative start up volume with a blest System Folder on it and valid boot blocks pointing to the folder. A Disk Tools floppy, or a full system (say a floppy disk containing System 6.0. 8) , will relieve you of trying to coax 6.0.3 out of ROM. If you haven't such a floppy (and you can download 6.0.8 here), in the meantime you should, if the HDD is spinning up, hold down command-option-p-r immediately after the POST (startup) chime, and release those keys only after the third extra chime.
This will reset the scrambled PRAM settings (which include the advice to Start Manager to look for an HDD at SCSI 0-0-0) resulting from a defective or absent battery, but will profit you only if there is a valid System Folder on an active drive at 0-0-0. The advantage of a boot floppy is that it bypasses possible SCSI woes because the FDD is polled first for a bootable System. A Disk Tools floppy will enable you to run Disk First Aid and HD SC Setup over the HDD, supposing that it can be mounted. If you can mount the HDD, you can check visually for a bootable System Folder.
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Do you hear or feel the HDD spin up? If it doesn't, you'll need an alternative start up volume with a blest System Folder on it and valid boot blocks pointing to the folder. A Disk Tools floppy, or a full system (say a floppy disk containing System 6.0. 8) , will relieve you of trying to coax 6.0.3 out of ROM. If you haven't such a floppy (and you can download 6.0.8 here), in the meantime you should, if the HDD is spinning up, hold down command-option-p-r immediately after the POST (startup) chime, and release those keys only after the third extra chime.
This will reset the scrambled PRAM settings (which include the advice to Start Manager to look for an HDD at SCSI 0-0-0) resulting from a defective or absent battery, but will profit you only if there is a valid System Folder on an active drive at 0-0-0. The advantage of a boot floppy is that it bypasses possible SCSI woes because the FDD is polled first for a bootable System. A Disk Tools floppy will enable you to run Disk First Aid and HD SC Setup over the HDD, supposing that it can be mounted. If you can mount the HDD, you can check visually for a bootable System Folder.
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