Can you install OSX on a USB hard drive and mac os 9 on the built in one?

You need to use an internal or FireWire drive. This includes partitioning the internal one.

(61649)

No, it won't.

(61655)

Not all iMac G4s are OS 9-bootable - the models released in 2002 are OS 9-bootable, but later models are not.

Those that are OS 9-bootable can use only the original OS 9 Software Install CD that came with it in order to install a bootable OS 9 (OS 9.2.2); they can not use any retail OS 9 Install CD. So, be sure to get the original disk set for the machine.

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The built-in USB on any Mac which is OS 9-bootable is USB 1.1; this is not upgradeable, and on an iMac there are no PCI slots in which an add-on USB 2 card can be installed. USB 1.1 is far too slow for regular use for booting. In addition, older machines, such as an iMac G4, are restricted to early versions of OS X which are not USB-bootable.

So, if you want to have a bootable external drive, the solution is a firewire drive, as Niel has indicated.

This is not a bad thing - firewire, even firewire 400 which an iMac G4 has, is far faster than USB 1.1, usually fast enough to use for a boot drive without suffering from delays. And, firewire tends to be a lot more stable than USB.

There are two iMac G4 models which are OS 9 bootable - the 15" released in January 2002, and the 17" released in July 2002. Both of those models were discontinued in February 2003.

Newer 15" and 17" models, starting with those released in February 2003, are not OS 9 bootable.

No, because the speed of a network connection is much slower than the internal speed of the hardware bus inside your computer that connects your internal disk.

The only network that is fast enough to match the inside of a personal computer is the networking hardware used by supercomputers, which is not priced for normal people.

I think I see where you're going with this...most home networks today are actually faster than USB 1.1. But the problem is, USB 1.1 itself is not even close to being fast...

You could put a Mac OS X image on another computer, and boot over the network. However, you will need another computer to do this, and fight your way through configuring it all to work. It is not so straight forward to do, so you'd be better off doing one of the following:

Install Mac OS X and Mac OS 9 on the same partition.

Partition the internal drive, and have one as a Mac OS 9 partition and one as a Mac OS X partition.

Put Mac OS X on an external firewire drive.

If you are really interested in doing NetBoot (as it's called), then post a question on the Mac OS X Server forum.

the built-in Ethernet is rated at 100Mbps and the Firewire is 400Mbps. With a modern 7200RPM drive you can probably get an external FW drive almost as fast read/write performance as the stock built-in internal ATA/66 5400RPM drive.

One thing to keep in mind when partitioning for OS 9, while you may not need that much space for OS 9, OS 9 won't boot from a partition larger than about 200GB.

You can boot a Mac from a network system. You can look it up...it's called NetBoot. Schools use it a lot. Works best with a fast network like Gigabit (1000 megabits per second).

USB 2.0 has a theoretical maximum throughput of 480 megabits/second. But it is normally far less due to its design. In practice, FireWire 400 is faster. USB 1.1 was 1.5 to 12 megabits per second.

For PPC generation of macs, you could install the system unto an external firewire drive, USB does not work (with the exception of a very limited series of macs delivered in 2002, if not wrong).

For your mac, the best option is to install Tiger or an earlier version of Mac OS X and Classic environment; if you still have the original CDs or DVds of that model, the Classic installer should be on the last CD/DVD of that mac. Check for it.

As an example, on my 2004 PowerBoo, I have two partitions, one with Tiger + classic, the other with Leopard. This is more practical and faster than using an external drive. If your internal drive has at least 20 GB, you may have two partitions, e.g. 10 GB for Tiger and 10 GB for Leopard. Tiger basic install requires 2 GB, Leopard double than that, sufficient for sunning essential apps and have the flavor of those days.