OS X on 300 MHz iBook

Le Big Mac

macrumors 68030
Original poster
Jan 7, 2003
Washington, DC
I have a G3 iBook, 300 MHz (about 3 years old). Currently running OS 9. Would it be a mistake to upgrade to OS X? Horribly slow? Acceptably fast (not as fast as the new machines, obviously). Any experience/comments welcome.



macrumors 68030
Jan 18, 2002
behind you
it depends on how much RAM you have. Jaguar runs VERY well on a snow iMac at work....I think it's something like 500mhz...??? Not 100% since it's my bosses and not mine, but it only gets a little slow if you're doing intense things. I believe it has 512 MB RAM but again I'm not sure.

So, depending on RAM it could do quite well. Another alternative (maybe, I don't know your situation) is to save up for/buy a new iMacif not now, maybe in a few months, your computer is getting a little on the old side. I'd say get a new one around the summer if you can wait that long, then you got 3 1/2 years outta yours and then you get a new one....with OSX!


macrumors member
Jul 17, 2002
on the sofa
OSX on my 366Mhz iBookSE...

I'm running OSX 10.2.2 on my grey iBookSE 366Mhz G3... and it rocks. In general it is quicker than 10.2.2 on my G4/400 AGP. Admittedly the iBook is not used for FCP or much P/shop work unlike the G4, but the actual finder feels punchier on the iBook. I haven't run any speed test, but I don't need to...

The iBook has 320Mb RAM and the G4 has 1.5Gb. Also, the iBook is only running OSX, not Classic.

I would recommend Jagwire on the iBook completely. The G3 is well suited to OSX as long as you're not using high end Pro applications that use the extra bells and whistles on a G4 processor.

Hope this helps.:)



Moderator emeritus
Nov 28, 2001
down in Fraggle Rock
i run osx on a g3 powerbook 333mhz. almost the same computer as your ibook. 66mhz bus and all.

i have used the computer for DP3, DP4, PB, 10.0, 10.1, and 10.2.

My machine has 512MB of ram and i think thats what makes it usable. Although I think 384MB would be ok as long as you stay away from RAM intensive apps. 256MB will NOT be enough though. I run photoshop on my powerbook regularly and find it fast enough.

i actually get impatient with the speed of os9 whenever i go back to it (i still need to go to os9 for viewing movies in full screen mode, gets choppy in osx).

OSX has a different kind of speed. it lets you do many things at once. while os9 does one thing quicker. So i often continue working while a file is being copied or a cd is being burned or any number of other tasks. Switching back and forth between apps is very fast and nice in osx. this is where os9 shows its age. sure windows will popup faster in os9 and your movies will play better, but osx will likely be a mroe productive platform due to the ability to multi-task.

Another thing to consider beyond speed is hard drive space. A standard install of jaguar takes 2GB. OSX needs free space on the hard drive for proper memory management in low ram situations such as you will encounter (try t keep at least 1GB free). So if your drive is small (4GB) you may not be able to use OSX.

lastly it is important in low RAM situations to reboot osx often (at least once every two days and as often as every few hours in high use situations). This is because osx will use hard drive space as ram and this slows down the system since hard drives are slower than ram. osx makes extensive use of ram so the longer you run the more ram you use. extensive use of hard drive to replace ram will slow down the system. rebooting is the only way to free up your ram.


macrumors regular
Jan 6, 2003
calgary, ab canada
we've currently got a g3 ibook running 10.2.3 and no problems at all. it's not a rocket by any means but it runs acceptably on 128Mb of ram. great if you are surfing, checking mail, doing docs in word or appleworks. if you plan to run illustrator/freehand, photoshop, quark it would be really taxed.

ram is dirt cheap right now, load it with ram and it's still a great little machine. apple's computer have such a long life, try running XP on a 300mhx PII. good luck.


macrumors member
Oct 1, 2002
Hollywood CA
I'm running 10.2.3 on a 350MHz G3 tower.... With 128MB of ram!! (the machine had 384 but one of the DIMMS was bad and was causing kernel panics)

It works.
It CAN be painfully slow at times when the OS is doing alot of swapping...

But over-all it isn't too bad... I put up with it because I really don't like OS9...

So, pack your iBook full of ram (and maybe a HD) and give it a go!


macrumors member
Jan 6, 2002
my advice

turn colours from millions to thousands
use Shadowkiller to remove shadows in X
Use Themer to install theme not using Quartz Extreme
Bang in a load of ram

watch it whizz!
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