[tpicco]

I have a G4 iMac... the kind that look like half a ball with a screen on a swivel neck. Bought it in Dec 2003. I cannot currently afford a new computer, and I am slowly slipping into the stone age, digitally. How far can I upgrade my Mac OS?

These are my specs:
Machine Model: iMac
CPU Type: PowerPC G4 (3.3)
Number Of CPUs: 1
CPU Speed: 1 GHz
L2 Cache (per CPU): 256 KB
Memory: 768 MB
Bus Speed: 167 MHz
Boot ROM Version: 4.6.8f4

Can I upgrade?
Do you need more info to answer?

[imitchellg5]

The latest version that you can upgrade to is 10.5.

[tpicco]

Can the OS 5 upgrade still be purchased? At Apple? Or elsewhere?

(Sorry I am so ignorant...)

[imitchellg5]

You can't buy it from Apple, but you can find it on eBay or craigslist. If you have any local Apple retailers (not Apple Stores), they may still have it in stock as well.

[hh.blitz]

Beware that Leopard might run mighty slow on your machine. The best OS in terms of performance would be Tiger (10.4), which is still semi-modern. But it might be hard to find a retail install disk. If you are going the Leopard way, I strongly recommend getting more RAM.

[Spheric Harlot]

Upgrading the RAM to the maximum of 1GB in those machines involves taking it apart and replacing the 256 MB stick on the main logic board - and then reassembling it with fresh thermal paste.

Not fun.

[Big Mac]

People will really be confused if you call it OS 5. It's OS X 10.5, or 10.5, or Leopard.

[Doc HM]

You can get 1GB ram modules to install externally (under the base) of these Macs. I would do that. And install 10.5. That way you are future proofing your Mac as much as possible. I suspect that support for and apps that run under 10.4 is going to get quite patchy quite soon.

As long as you aren't expecting fireball performance you should do fine. What ever OS you choose don't expect it to handle flash at all well. You may find YouTube beyond your machine's abilities.

[zerostar]

I tried running 10.5 on a 1.5GHz G4 Powerbook with 1.5GB Ram and it was VERY VERY slow. I went back to 10.4 and while it wasn't "blazing" it was much better and I use it almost daily on the couch... I would stick with 10.4 or consider upgrading...

[Big Mac]

That's a weird experience. You shouldn't have any problem running 10.5 on a 1.5GHz G4. Maybe it was Sherlock indexing that you got hit with that slowed things down initially, before you got a chance to use the system normally.

[Eug]

I run 10.5 Leopard on all of my G4 Macs. Click2Flash helps immensely for Safari to speed things up.

The very LEAST you should run is 10.4.11. Too many compatibility issues with 10.3.

The only hardware upgrade I'd do with that iMac is add more memory. A hard drive upgrade would help, but it's a huge pain to do, and if you're going to upgrade both the memory and the hard drive the cost is starting to add up. That said, if you do replace the hard drive, you'll get the chance to clean out all the dust that is in there clogging the air vents and the fan. This can quiet down the iMac if your iMac is loud. (Even though I did replace the memory and hard drive, it was just because I wanted a functional iMac that I could keep for nostalgic purposes, and I had the extra money to burn.)

However, if you really want a speed boost, and don't want to spend too much money, save up some money and then sell the iMac, and buy a used Intel Mac mini with a cheap monitor. Once in a while you can pick up an Intel Mac mini for under $400 with a 3 month warranty. Even a lowly Core Solo would blow that machine away. I'd recommend the cheapest dual-core Mac mini you can find though.

[l008com]

Switching the dock from the reflective, 3D dock to the "noglass dock" speeds up 10.5's interface A LOT on PPC macs. With the default dock, things are very laggy.

Also, upgrading the internal memory slot isn't hard at all, you just need... I believe a T10 driver. If you're going to upgrade at all, you might as well go as new as you can. 10.5.8