Unable to boot

My G4 froze as I was working, and a hard reboot was required. At first it looked OK with the grey apple logo and revolving wheel. However it stayed like this for a good 2 minutes. I was then presented with a blank blue screen and a small revolving wheel icon. This continued for several minutes after which my cursor was displayed, (controllable with the mouse). After a short while the wheel reappeared, and this went on for a good half hour. Eventually I was given a login prompt (Darwin/BSC (macg4.local) (console) login.
I typed in what I thought was my system login and password. But this was not accepted. I have tried the whole process several times. I have also tried holding the Option key on startup and manually selecting to boot from the hard drive.
Has anyone any idea what's going on here please?

Welcome to mac-forums, sorry it is under such circumstances! Sounds like a dying hard drive, although the fact that your user name/password isn't accepted is a bit odd. Do you have your Tiger installation disk? Pop it in, reboot, do the option key trick and select the Tiger disk. Don't do the installation, go to the menu bar, Utilities, select Disk Utility. What is the SMART status? Can you run Repair Disk? Do not run Repair Disk Permissions.
Good luck!

Unfortunately my install disc is elsewhere at the moment, so I can't try that. But thanks - I'll give it a go when I have it. I don't suppose you can suggest something else in the meantime....

Nothing I can think of without an install disk. Even buying something like Disk Warrior, which is a great product, you will need that install disk at some point.

Just wanted to give some feedback on this posting. The disk repair utility from the install disk did the trick like magic, and I'm back in business. Thanks Sherman and greetings from the UK.
Richard

Right back at ya!
Glad it worked!

However...............
I think the same problem has happened again and I'm going to have to nurse the machine to take backups of my data and start from scratch on a new disk.
Question: Will any hard drive work on Apple hardware, or only specific makes/models?

Ah, too good to be true. Most hard drives are not specific to Mac/PC/linux, whatever. The G4s had a couple of variations, what model do you have? You may find that even with the expense of a controller card, a SATA drive might be a better option.

Not sure what you mean by which model (excuse ignorance!). It's a pretty standard G4 desktop with 1gb mem and 800mhz processor speed.

If it continues to happen an Archive install of the OS could solve a few things

The G4 with a 800MHz processor is a QuickSilver 2002 model. You are in luck with the drive support, it will take a ATA-66 drive bigger than 128 gigs. Earlier models couldn't see anything larger than that. And I do think you need to replace that drive before it completely melts down.
Incidentally, it will take three 512 PC133 chips, max it out when the hard drive ordeal is over!

I've managed to back up my data which is a relief, and yes, I'm going to replace the disk ASAP. I'm a bit confused over the ATA/PATA/SATA side of things. Presumably, if I go for SATA I will also need a controller card, but not for the other types?

You are looking for a 3.5" IDE ATA hard drive. You can pop in a SATA controller card and use bigger cheaper SATA drives, but make sure that you get a card that supports booting a Mac. I would bump that ram up to the 1.5 gig max. Then all you have to do is decide if it is worth putting a few hundred into a Mac that won't run Leopard...
;D