iMac G3 (tray loading)

Way back in Jan of 2016 I wrote an article on the slot loading iMac G3. This time we’re going to take a look at the original Bondi blue “tray loading” iMac G3 and see how this iconic computer that is often times referred to as “the Mac that saved Apple” compares to its later “slot loading” revision. In this article we will be looking at a more or less bone stock very first revision or revision A model originally released in August of 1998.

As I stated in my original post on the slot loading variant of the iMac I was not the greatest fan of the Mac and was firmly in the Wintel PC camp during that time. My disdain for the iMac though was at the height of my displeasure with all things Apple and I honestly did not know why anyone would want one of those computers. Time and experience though has softened my stance and I now can appreciate these computers for what they are and the use they were intended for. The all in one iMac G3 was not a new idea but it was an idea that Apple as a company had moved away from during the latter half of the ’90s to make more generic “PC” type machines and hence lost a lot of what made Apple unique and stand out in the market. The iMac G3 was an all-in-one machine and was extremely simple to set up and played with Apple’s strength of focusing on industrial design with a colorful and inviting Bondi blue colored shell as opposed to the standardized beige of almost all other PC cases. The iMac was intended to be extremely user-friendly and be simple to set up like a microwave or a toaster. This computer was aimed at the average user just wanting to “surf the net” or write school assignments rather than power users or gamers (even though the iMac certainly could be gamed on).

The original model seen here only came in Bondi blue as opposed to later models that were offered in a variety of colored shells. A handle was provided at the top to help move the Mac around but to be honest it always feels a little awkward to use and I always feel like it’s going to snap off despite the handle being very sturdy.

The bulk of the iMac is taken up by the built-in 15-inch shadow mask CRT monitor capable of resolutions up to 1024 x 768. The iMac G3’s kept this same spec monitor throughout all models though later slot loading iMac’s supplied an external VGA port to connect to an external monitor. These early tray loaders did not which makes it quite unfortunate if your monitor dies. The rear of the Mac hides only a small handle, which is used when removing the motherboard, and a standard 3-prong power connector.

They also came with a matching Bondi blue iMac keyboard and mouse. The keyboard is a simple Apple USB keyboard and is not so dissimilar from others besides the color but the mouse, a USB ball type mouse, is the infamous “puck mouse” so called because of its hockey puck like shape.

Unfortunately the rumors of the poor ergonomics of the of the puck mouse are completely true and the mouse can be very awkward and uncomfortable to use over any extended period of time. This isn’t a major problem since the mouse can be swapped out with any Apple USB mouse including later Apple Pro mice which use a standard shape and sports a laser as opposed to the older ball for tracking. The puck mouse also uses the traditional one-button Apple style mouse so no scroll wheel. The mouse has held up well though I’m not sure if this is from rugged construction or lack of use.

The iMac was famously the first Mac to drop the floppy drive although one was easily added via a USB port. In its place a 24x CD-ROM drive was standard and is located below the monitor. The early runs of the iMac used a tray loading CD drive, hence the “tray loader” title where as the later models used a self-loading slot mechanism. Next to the CD drive we have a power button that emits a soft green light when on and on the right and left sides we have two built-in stereo speakers. These speakers do have a habit of rotting a bit but it is a repairable issue and fortunately this particular iMac does not suffer from the foam around the speakers deteriorating.

The speaker on the left has a wireless 4Mbits/s IrDA inferred sensor which was removed starting with the revision C tray loaders. The right speaker has dual 1/8 stereo jacks for hooking up headphones that two users can use at once which is quite nice. Underneath the Mac is a fold-out stand of the same Bondi blue as the case.

On the left side of the iMac we have a small compartment housing some various ports. The is a plastic cover which can either be removed entirely or replaced after your various peripherals are plugged in and the wires snaked out through the several openings provided.

Once the plastic cover is removed we are greeted by a variety of ports.

On the left we have two more audio jacks, one for a microphone and a second for optional external speakers, handy if the built-in speakers fail or are not powerful enough for your liking. Next to that is a scant two USB 1.1 ports. The iMac is also known for going all in on USB and ditching the traditional Apple ADB ports in favor of USB though I wish more USB ports were made available. The mouse is generally expected to plug into the USB port on the keyboard (this why the cord is generally so short) and this does help free things up. A USB hub can also be used without issue in case you have multiple USB devices you want to use. Next we have a 10/100 Ethernet jack and lastly a 56k Modem jack.

Under these ports we have a mysterious little covered cutout held in by two screws. Behind this cover is what is commonly called a “mezzanine slot”. This is a sort of expansion slot that originally was only supposed to be for Apple’s internal use but you can use it for other things and third parties did make expansion devices that took advantage of the presence of this slot though from my research they seem to be extremely rare. I even know of at least one third party adaptor that uses the slot to add a 3DFX Voodoo II upgrade and according to Wikipedia SCSI and TV tuner cards were also available though I’ve never seen any of these cards in person. This port was removed along with the previously mentioned inferred sensor with the tray loading revision C model.

Opening the iMac is much easier then it is on later revisions and there is no “mesh” layer present that requires removal. You just need to remove a few screws on the underside and then use the handle to pull off the plastic case section. Once the outer case is removed as well as a few more screws and cables the motherboard assembly will slide out though be careful as with most older Macintosh computers the plastic casing can be delicate and things tend to snap off.

Here is the underside of the case with the motherboard assembly removed. The early tray loaders sport a fan for cooling as seen here while the later slot loaders used a fanless convection process to cool internals.

Here we have the tray that holds the motherboard and most of the iMac’s components completely removed from the case. The hard drive is located under the CD-ROM drive as seen in the image below. Mine came with the original 4GB 5400 RPM drive.

Originally the iMac came preloaded with Mac OS 8.1 or 8.5 with the ability to officially upgrade to OS X 10.3.9 though mine has been upgraded to OS 9.2.2.

1 ) CPU/RAM – The CPU and RAM on the tray loaders were both located on daughterboards that connected directly to the main motherboard. The metal cage enclosing the daughterboard easily wiggles off with some light force. Revision A as seen in this article and revision B iMacs only shipped with a 233MHz PowerPC 750 G3 processor w/ 512kb of L2 cache but later revision C and D tray loader iMacs had 266MHz and 333MHz CPUs installed.

CPU module top

CPU module bottom

Standard RAM amount was 32MB of PC100 SDRAM in a smaller laptop style form factor. The revision A iMac was expandable officially to 128MB and unofficially to 384MB. Revision B, C and D were officially expandable to 256MB and unofficially to 512MB. My machine came with the oddly numbered 288MB of RAM installed. It seems the previous owner did make the sole upgrade of adding a 256MB stick of memory in addition to the 32MB of RAM already installed.

I had no problem up upgrading my RAM to a full 512MB by installing two 256MB RAM modules despite being a Rev. A motherboard and sources online indicating 384MB being the limit.

2) Video – Original revision A iMacs shipped with a built-in Rage IIc chip and 2MB of SGRAM as seen on my iMac but this was quickly changed in revision B and up tray loaders to the much more powerful Rage Pro chipset with 6MB of SGRAM standard. The original revision A boards can be upgraded to a full 6MB of SGRAM.

The ATI chip isn’t a surprise as Apple has a history of using ATI chips for graphics in this era. As far as I can tell the revision A iMac G3 is the sole computer to use this specific version of the Rage chip built in. Overall the Rage IIc is an adequate chip, though by 1998 it was getting quite outdated and was seen as a entry level 3D video chip. 2D applications should run just fine as well as less intensive 3D titles as long as resolutions and features are kept in check.

with 4MB extra video RAM module

3) Sound – Sound has always seemed like a bit of an afterthought in Apple machines and finding specifics has always been a bit of a chore as sound chips aren’t commonly noted on spec sheets. The iMac would appear to use Crystal CS4211-KM chip which supports simulated surround sound via the two built-in speakers.

4) Battery – Lastly we have the PRAM battery which acts just like the CMOS battery in a standard motherboard. Be sure to replace this on any newly acquired Macintosh computer.

Accessories

Compucable iDock II

The iDock is an interesting accessory that was designed for the iMac to extend its capabilities. My version is the iDock II which features a built-in 1.44MB floppy drive. As far as I can tell the floppy drive is the only difference between the iDock I and II. The iDock connects to the iMac by way of a standard USB cable and requires its own power supply.

The top of the iDock swivels allowing you some measure of turning your iMac which sits on top of the iDock.

The rear of the iDock features several ports to expand your iMac such as four USB ports, two Geo ports and one ADB port. The ADB port has been reported to not work or only partially work on these units. On mine I was able to get an ADB mouse to work but it was very iffy and the response was poor. The iDock does require special drivers to function.

The iMac does what it set out to achieve and I can see now what I couldn’t see as my high school self, why the iMac succeeded. It wasn’t meant for people like me. It was meant less for hardcore PC gamers and those that liked to expand and tinker with their computers and more for the everyday user, the soccer mom, the person that just wanted to do homework and surf the internet and it made a pretty easy to setup and usable computer to sit in the corner of the family room and have for general family usage.

As a collectors piece the Bondi blue iMac is certainly worth adding to the collection and holds a significant place in computer history and especially Apple’s history. They are still relatively inexpensive as of 2019 though an original revision A may take some work track down and identify. If your purely looking for a Macintosh for late 90’s gaming though there are much better options. Personally, I think your better off acquiring a Power Macintosh G3 tower or desktop simply for the vastly greater options you get in upgrading (such as PCI slots) and higher ease of repair. Failing finding one of these a later slot loading iMac or even a G4 could make a good choice as they seem to be easier to source and are more powerful out of the box.

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iMac G3 (Slot Loading)

Growing up I never considered myself a “fanboy”. Even at the height of the 16-bit console wars I never took sides. Sure I preferred the Super Nintendo and considered it the better system but I generally didn’t belittle or shun the Sega Genesis and still wanted and was happy when I received one. This was the general trend with me as far as video game consoles were concerned. I had my favorite that I preferred but I always felt every console had something to offer. Then enter the PC gaming side of me. In my youth I will admit I was an unashamed PC “fanboy”. Ive gone into this before with my previous Macintosh posts as well as said how over time I have grown to accept Macintosh machines and acknowledge they have their place in the great computer scheme of things. I felt I needed to restate this though because of all Macintosh machines no other machine earned my irrational hated and scorn like the iMac G3.

Back in the very late 90’s and early 2000’s I could not comprehend why anyone would want one. To a younger me that couldn’t appreciate the industrial aesthetics as I can now they looked and felt like cheap toys. I felt the playful translucent color schemes were childish and cheap looking. I felt the machine was ridiculously limited in its upgrade options and also overpriced. Why in my own mind would anyone pay a premium for a machine that you could barely upgrade? Of course this is before I came to understand Macintosh as I do now, to appreciate the design and simplicity. You must understand as well that back then as well as now I was primarily a gamer. The computer to me was more a machine for playing games then it was for work, artistic pursuits or perusing the world wide web and as a game machine the iMac generally falls behind when compared to a PC with its massive amount of video card acceleration options as well as bountiful expansion slots and drive bays.

Flash forward some 14 years. I am much more accepting of the Macintosh now and own several, from classic compact versions to late 90’s 7500 machines. One day as part of a computer lot I was picking up I was given a iMac G3 and there it was, my old enemy. Even after all those years I still felt a strange disliking for the thing, “Pointless toy for teenage girls and people that know nothing of computers. Only  fit to surf the web and do homework on, not a “real” computer”. Yet here it is, setup in my apartment where I have very little space. As a matter of fact it is the only Macintosh machine I currently have set up and it has replaced my Mac 7800 as my primary late 90’s Macintosh. Honestly the thing kind of grew on me for the very reasons I once shunned it, simplicity and its interesting design, such irony.

As a gaming machine I still say its is limited compared to its PC contemporaries but really the Mac never was a meant as a ultimate gaming rig and for late 90’s Mac exclusive titles or “Macintosh enhanced” versions of games the iMac G3 is just fine.

There are actually several versions and revisions of the G3 iMac. The greatest version differences though are from the early CD tray loading models and the later slot loading models. I do not own a tray loading model so that may be for a separate review but I do currently own two later slot loading models which differ slightly in design that I will go over now. Both models I own are “indigo” colored models. one being a lesser powered 350mhz version and the other being a more powerful 500mhz version. These machines differ in ways other then CPU speed which I will discuss.

The slot loading models came in CPU speeds ranging from 350 – 700mhz. The machine shown above that I have setup and game on is actually the lesser powered 350mhz model. I chose to use this model for a few reasons. First is for the era of games I’m playing which will be mid to late 90’s a more powerful CPU is really unimportant. After all the machine this replaced was only running a 300mhz G3 at a lower FSB and it performed exactly how I intended. Anything that needs a faster CPU I’ll just use the G4 Mac I acquired.  Second the faster model I own is in considerably worse shape then this model. Its internal speakers are almost dead and its plastic shell is chipped, faded and overall degraded.

So looking at the machines its pretty obvious that this is a “all-in-one” type machine harking back to the original concept of the Macintosh. This is both a blessing and a curse. The up side is the very small footprint this machine takes up on a desktop, at least without anything added such as external speakers and external USB drives. Its extremely simple to setup and only requires a single power cable. The downside of all this is if something fails your pretty much screwed. If the monitor dies on a more traditional setup you just replace the monitor. On this machine if your monitor dies your screwed…well for the most part but I’ll get to that. It also makes the machine very cramped inside and difficult if not impossible in many cases to upgrade.

The monitor is a 1024 x 768 pixel resolution CRT which I’ve found to be adequate in most situations. There is a built in slot loading CD drive bay and that’s about it for built in drives. Most iMacs came with a CD drive but there were models with DVD drives and you can upgrade CD drive versions with DVD drives. Unfortunately I’ve found identifying which model slim DVD drives will work and fit in the iMac to be difficult to figure out over the internet. Below the CD slot we have two headphone audio jacks and to the right a power button. On this model the power button glows a traditional green when powered on but on my 500mhz model the power LED is white.

On the bottom left and right we have two built in speakers. Ive found the built in speakers to be fairly weak and worse yet many of them have degraded considerably over time and have become static filled popping messes. This usually due to the foam around the cones disintegrating over time. Also in my attempts, replacing the speakers seems an almost impossible task. Go ahead, try it if you have one with bad speakers, all I can say is good luck. I found some vague references to latches and having to push down and twist but all my efforts to remove the speakers for replacement proved futile. I was to afraid to snap something as the pressure it seems you need to apply seems excessive. Not even mighty YouTube had a video showing speaker replacement on these things as of the writing of this article. Thankfully this issue can be bypassed by use of external speakers. I would recommend a good pair of external USB speakers to keep the concept of desktop clutter down. There is also a little plastic stand on the bottom of the unit that works as it should. I should also mention the nice carrying handle on the top of the case as well as the fact these machines are fanless so their whisper quiet.

Originally the iMac was sold with a round USB “hockey puck” mouse but these weren’t very well received and a little awkward to use. Later units were sold with the black optical USB Apple Pro mouse like the one I’m using here. These mice were prone to failure due to “flexing and corrosion” so be mindful of that. Later white revisions of the mouse solved these issues. I am using my Pro mouse with a Pro keyboard from around 2000, contemporary with this machine.

This was one of the first computers to finally ditch the floppy drive as standard. Thankfully if you still have a use for floppy drives and disks USB floppy drives were actually made specifically for the iMac and many drives even included color covers that could be swapped out to match your machine. My drive is by VST and you can still find them relatively cheap on eBay boxed. I paid about $12 for mine still sealed.

On the right side of the case we have our various connectors. Two for USB 1.1, two audio jacks for a microphone and speaker as well as a jack for ethernet and a modem as well as a restart button and a “programmers button” that gives access to firmware. On the later 500mhz model you can see two firewire 400 ports were added.

Your likely going to be relying heavily on external USB devices to expand the capabilities of the G3 iMac. Two USB ports doesn’t seem like much in this situation but luckily there are more USB ports on the keyboard as well as the option to use a USB hub device. I keep my keyboard directly plugged into the iMac with my mouse plugged into the keyboard USB port. For any other devices such as my speakers and floppy drive I have a USB hub device plugged into the second jack and those devices running from the hub.

Alright so lets open these things up and see whats inside. To open the iMac you need to flip it over and unscrew the base to get to the motherboard.

CPU – first I’m going to talk about the CPU which I don’t have numbered on the images. To the best of my knowledge it is located on the underside of the motherboard. All of the slot loading  iMacs G3’s run on the PowerPC G3 CPU with a 100mhz front side bus. The models I own are running a 350mhz PPC 750 G3 and a 500mhzmhz PPC 750cx G3. Personally I always liked the power PC line of CPU’s and the G3 is perhaps my favorite. Don’t be fooled by the lower clock speed as these will smoke a 350mhz Pentium II as well as draw less power. More then capable of driving 90’s gaming.

1) Drive tray – This where your slim CD/DVD drive goes as well as the hard drive. The iMac takes an IDE hard drive. Mine was 20GB but I upgraded to an 80GB drive and installed OS 9.2.2 for the best late 90’s game compatibility. I also made a smaller 20GB partition with OS X installed just for fun. I don’t use OS X much on these machines because I do find it runs a tad slow especially on my 350mhz Mac.

2) RAM – The G3 iMac takes PC100 SDRAM and usually came with 64MB or 128MB. This can be upgraded to a max of 1GB via the two 512MB sticks as I have done in the images above.

3) Graphics chip – All versions of the slot loading iMacs use some variation of the Rage 128 chip. My 350mhz iMac sports a Rage 128 Pro with 8mb of RAM while my later 500mhz model has the Rage 128 Ultra chip with 16mb of RAM. Video on the iMac is not upgradable so your pretty much stuck with what you get. That said the Rage chips aren’t bad. They are more then adequate for playing any games from the late 90’s though competent but unimpressive for post 2000’s.

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Now to address the things that are completely lacking on the earlier revision of the slot loading iMac. On opening these machines I was actually surprised how similar yet different these motherboards were. First off if you look at the 500mhz motherboard there are two items circled in blue. The white connector by the RAM slots is a port for a wireless AirPort card. These cards are still compatible with the older revision with an adapter. The second item circled is an actual VGA out port. This is a very welcomed addition as I assume this would allow you to use a separate monitor if you wanted or if the built in monitor died. Personally I think this thing would look very awkward being treated as a tower with a separate monitor but it is a very nice option to have included.

before I conclude I also wanted to show this handy program I have installed.

That’s something you don’t necessarily see every day. I ran across this program at a thrift shop and its pretty nice. This would of been very handy back in the day if all you had was a Macintosh. The program has sound blaster and USB support and it actually makes transferring files across OS’s pretty convenient. For me its mostly a curiosity since I have plenty of Windows 98 machines but its nice to have even if it does just feel wrong.

So what are my final thoughts? I certainly no longer hate the iMac G3 but I still don’t feel they made great gaming computers even in their day. Then again that was never the purpose of these machines. They are beautiful and interesting to look at in an industrial design way and have very little desktop clutter especially without a floppy drive or external speakers but again they are so very limited in expansion options. As a platform for playing 90’s Mac games though It does quite well. It’s kind of a toss up though between this and a beige G3 for 90’s gaming. The beige G3 offers much more expandability in the way of video cards and monitor but internally is an overall slower system with a lower FSB and comes with more cord clutter. For someone like me that is really only interested in a few 90’s mac exclusives and Mac “enhanced” games the iMac G3, a once dismissed machine has ironically become the computer of choice thanks to its small footprint.