Upgrade HDD in an old G3, using firewire dr.

Feb 5, 2010
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I am having all kinds of fun tinkering with my old iMac G3 Ruby 450mhz. Over the years, with the help of this forum, I successfully kept upgrading it. Now I'm at again! I'm putting in 1gb of memory (found some REALLY cheap); and am toying with the idea of upgrading the 5200 rpm 40GB hard drive to a faster 7200 RPM 80 GB Seagate Barracuda (New: $27.) Supposedly I will have then done all that is humanly possible to eke out every last drop of speed from this ancient beast of a computer (which I'm fond of).

The last time I upgraded drives, from a 20gb to a 40gb, I used my external fire wire drive and carbon copy cloner to do the job. I still have the external fire wire drive with OSX 10.4.11 on it, and the computer will boot from it just fine.

So.....is this what I now do?
1. take out the old 40 gb 5400 hard drive
2. replace it with the new Seagate 80gb 7200 rpm hard drive.
3. Boot up the computer from the Fire wire drive.
4. Look for the new Seagate 7200 hard drive.
5. Partition it.
6. then what? I'm sorry, i just cant' remember how i did it before.

Thanks, Everyone,
Nov 28, 2007
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Blue Mountains NSW Australia
Your Mac's Specs
Silver M1 iMac 512/16/8/8 macOS 11.6
The drive will be fine - did that eleven years ago with a 350MHz slot loader. After formatting and partitioning, use the 5400 in an external case connected by Firewire and SuperDuper or CarbonCopyCloner to make a clone.

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