I posted this to a mailing list that I'm on but have got no reply. Perhaps somebody here could set my mind at rest.
I recently (well, about 4 or 5 months ago) bought a G4 Dual 500 and it was in the same state as when it left the factory. It had a Maxtor 40GB hard drive and I quickly realised that it wasn’t going to be big enough so, last week, I bought a new 120GB IBM Deskstar to fit as a second drive. I was a little wary of installing it, as my other Macs have all been much older and I've only been used to SCSI drives. Anyway, I looked around the web for reference material and found an instruction page on www.xlr8yourmac.com and had a read. I bought the drive from www.ebuyer.com and it was very cheap. It only came in an anti-static bag and an unmarked brown box. There was no documentation with it (I wasn't surprised as it was so cheap). I left the original Maxtor with it's factory jumper settings, which left it set as unit 0 (master). I changed the new IBM jumpers so it'd be identified as unit 1 (slave) and started up the Mac. I launched Disc Utility and was horrified to see that it could see both drives, but it was seeing the new drive as 0 capacity and I (not surprisingly) couldn't do a thing with it. I powered down and unplugged the original 40GB drive and set the jumper settings of my new one so it'd be recognised as unit 0 (master) and booted from my OS X (10.1) CD. This time, the disc utility formatted it and I was able to partition it into four volumes. After I'd done this, I shut down and changed the jumper settings of the new drive and plugged the 40GB Maxtor in again and powered up. This time, everything seemed to be working fine. The four new volumes appeared on my desktop and disc utility could see both drives correctly, as master (40GB) and slave (120GB). All seems to be working fine now but I wonder if somebody could set my mind at rest. I'd hate things to go belly up in a couple of weeks.
If it works fine now, then there's nothing to worry about. My guess is that your new hard drive simply wasn't formatted, so OS X couldn't recognize it correctly. Once you partitioned/formatted it with the Disk Setup Utility it could then be 'seen' and used correctly.
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