Recovery of an Overheating Power Mac G5 Quad

Some time back, I did two posts on the apparent death, and then partial recovery, of my much loved Power Mac G5 Quad.

G5 Quad

In A Casualty on the Front Lines I described discovering the machine one day with its fans running at full blast, and the CPU temperature meter hovering in the 80’s C. I shut it down immediately, assumed rather too quickly that it was done for and deduced that there was no course left but to harvest all the valuable parts I could from it and put the carcass out to pasture.

In The Reports of My Demise Are Greatly Exaggerated, urged on by reader Ty (author of the now defunct Resto-Bytes blog) to not give up without a fight, I made an initial effort to find and repair the cause of the problem, which at the time I assumed to be a failure of the G5 Quad’s infamous Liquid Cooling System (LCS). Instead, what I found was dust, and lots of it, obstructing free airflow into the CPU area of the machine.

Dusty Grill

This aligned perfectly with the blistering CPU temperatures and the full speed fan rotations and so I carefully cleared all the dust out and closed the machine back up, confident that it would now be back in the land of the living. I was wrong. It improved, but the CPU temperature stabilized in the low 60’s C region, and the fan rotations at their full value of 3600 RPM. This was both too hot and too noisy to allow me to return the G5 to full service.

Clearly I needed to get into the CPU area and get at a presumed accumulation of dust there before I could restore fully normal operation. The machine wasn’t dead anymore, but it was far from healthy.

I downloaded the G5 Quad service manual from the web and reviewed what needed to be done. It did not look like a trivial undertaking and I did not have the time just then to do anything more complex. So, I backed up the G5 Quad, restored it onto my similar vintage G5 Dual and put that machine back on line (the G5 serves as the Happy Macs Lab online Gopher server, and so it plays an important role, requiring a stable and reliable machine).

This remained the state of affairs for the next many months. Finally, I recently had the time to undertake that next step and see if I could recover the G5 Quad back to full functionality. With all of this as preamble, this post details the steps taken and the results achieved.

I started by opening the G5 Quad’s side access panel and removing the clear plastic air deflector. Anyone who has ever looked inside a late 2005 G5 will be familiar with these steps. Next, I extracted the front inlet fan assembly, which can be directly lifted out of the case with only a light amount of force. Now I had unobstructed access to the CPU area.

The CPUs and their all-important LCS are protected by a metal panel with the iconic “G5” lettering emblazoned on it. Apple calls this the Heatsink Cover.

1.Heat Sink Cover In Place at Start

To get at the CPU area, this cover has to be removed. This sounded simple enough in the service manual. All that was required was to locate the plastic rivet that secured the cover to the PCI divider plate directly above it, pry up the rivet’s center post and then pry up the rivet itself. With this done, the entire rivet could be extracted. With the rivet out of the way, the heatsink cover could then be removed by sliding it forward and lifting it up and out. Like all too many things however, this turned out to be quite a bit more difficult to do than to say.

I found the locking rivet easily enough. It is located at the top right of the CPU area, along the flat top surface, and was such a good color match with the rest of the panel that you almost wouldn’t notice it if you weren’t specifically looking for it. Aesthetics were everything for the Apple of 2005!

Per the service manual, I used a long handled Xacto knife to gently pry up the rivet’s center plug. This took multiple efforts and a little finesse, but in the end it was a fairly simple operation. The outer casing of the rivet itself was another matter entirely. While I managed to pry it up from the surrounding plate with some effort, I could not get it to come up far enough to extract it. Any part of it that I touched with the tips of a small pair of pliers would just come apart. Ultimately, the remains of the rivet simply fell into the housing, solving my immediate problem. The service manual did note that the rivet needed to be replaced during reassembly, which was clearly going to be a problem now, but hey, one step at a time.

With the rivet now out of the way, I was able to slide the Heat Sink Cover forward and then lift it out, leaving me with unobstructed access to the inside the CPU area. Regrettably, the hoped for accumulation of dust was nowhere to be found, and with it, any simple explanation for the overheating I was observing. I checked the LCS itself carefully, but there were no signs of leakage from it, and no obvious external damage. Since the LCS appeared to be in an excellent condition, it was probably not the culprit I was looking for.

Then I noticed a small pile of black debris lying right along the front edge of the fan inlet area.

3b.Debris Pile and Insulating Mat (Annotated)

Where had that come from? Well, there is what appears to be a thin insulating mat running along the bottom of the processor area and parts of it seemed to have disintegrated over time. The small pile of black debris appeared to be from that source. Now all that debris was sitting quietly in a tidy little pile with the machine turned off and opened up, but when it was closed and operating, this set of debris was in all probability plastered all over the inlet or exhaust areas, held in place by fan air pressure. This would very effectively obstruct airflow. Had I found a possible villain? I thought so.

I used two long handled screwdrivers as opposing clamp pieces to gently pick up and remove the debris. I got most of the large pieces out this way, but far too many times, the pieces had a tendency to come apart as they were being lifted out and then fall back into the CPU area in a shower of smaller pieces. The material had a very fine consistency, almost like dust in some cases, making it very hard to get a grip on any one piece without simply breaking up that piece. Regrettably, any physical contact with the insulating mat itself caused more pieces of debris to fall off, and as a result, it became almost impossible to get all of the debris out.

Ultimately, I resorted to a vacuum with a long thin nozzle attachment and gently vacuumed the area out, avoiding as much contact with the insulating mat as I could. While I had a vacuum engaged, I also re-vacuumed the fan filters at the front and back of the CPU area. When I was done, despite my best efforts to avoid contact with the insulating mat, there was a significant chunk of it now missing.

5.Damaged Insulating Mat at End

Other than that, all looked well, and certainly much better than it had when I first opened the G5 Quad up. Time to sew the patient up and see if this was a cure! I replaced the processor Heat Sink Cover, albeit without the now broken rivet, put back the clear plastic air deflector and finally closed up the side access panel. I reattached all the relevant cables and hopefully pressed the front power button. There was no startup chime, but nonetheless the machine fired up and quickly came to the Tiger desktop.

I am happy to report that the net result was something approaching complete success! After boot up, the CPU temperature started displaying at 53C, but then much to my distress quickly shot up to 63C. Just as I was about to declare defeat, it started to come back down. After ten minutes, the G5 was idling at about 51C with the CPU fan speed being reported as 1310 RPM. This was a HUGE improvement over my last effort, where the results had been mid 60s and 3600 RPMs.

In order to decide what “success” actually looked like, I decided to check my original install logs and see if I had taken any temperature and fan readings from the G5 when I first got it. Sure enough I had, with iStat Pro used as the source. Immediately after I installed Tiger on the G5 in 2011, iStat Pro reported 50C to 51C as the idling CPU operating temperature, and 1250 RPM as the CPU fan speed needed to maintain it. So, eight years and a little repair work later, it was once again 50C to 51C, but the CPU fans were working a little harder to keep it that way. Not a LOT harder, but a little harder… running 4.8% faster. It would seem that “success” had been achieved after all! Not bad for a 15 year old machine that I was about to strip and put out to pasture!

What can I say except” Welcome back to the real world, G5 Quad!”, and thanks to reader Ty for encouraging me to soldier on. A fine old machine is back on its feet again as a result.

Looking forward, I keep promising to report on the work I did with another now much loved machine, my Macintosh IIfx. In the interim however, I have diverted to Snow Leopard, to networking older Macs and now to the rescue of this G5 Quad, but I have not lost my thread. There is one more short post coming on Snow Leopard, and then we will return to the Macintosh IIfx theme. Stay tuned.

Networking Older Macs – Link Speed Auto-Negotiation

After my last post providing the back story of the Macintosh IIfx, this next one logically ought to concern itself with my efforts to dual boot System 6 onto a Mac IIfx that was delivered with System 7.5.5 already on it. However, as happens all too often, I ran into a roadblock right out of the gate. Despite the presence of a networking card that the seller assured me was fully functional, I was unable to get my Mac IIfx to connect to the Happy Macs lab internal network. Resolving this matter unearthed an issue of some small interest, Ethernet link speed auto-negotiation, and so as a prelude to dual booting System 6, I will delve into this somewhat arcane topic for just a moment.

I have used a vintage Linksys 10/100 switch to connect most of the older Macs in the Happy Macs lab with no troubles at all. The oldest of the Macs thus connected is a Macintosh IIsi running System 6.08, and connected via an Apple networking card (Apple Ethernet Twisted-pair transceiver M0437LL/A).

Linksys 10_100 Switch (Reduced)

The “new” Macintosh IIfx came preloaded with Mac OS 7.5.5 and a Farallon EtherMac II-TP networking card. The seller confirmed that the machine connected to his local network just fine, and in fact included pictures of it running an early web browser.

Farallon EtherMac IItp

Therefore, one of the first things I did with this machine was to hook it up to the internal network of the lab via my proven Linksys switch. Since I am writing a post on this topic, it will come as no surprise to find that this did not work!

I was not overly concerned to start with, assuming some form of software configuration issue. Since I was going to reload the machine with System 6.08 anyway, I decided to wait until I had done so before getting too involved in trying to get networking up and running. In due course, I did in fact load the Mac IIfx with System 6.08, replicated the networking software configuration and settings that were working so well on my Mac IIsi, and then wondered in frustration why it would work so well on that machine but not at all on the Mac IIfx!

I focused immediately on what was different and relevant between the two – the networking card. I found Farallon drivers for it and loaded those, to no avail. I tinkered with the software lineup and configuration, again to no avail. I began to suspect that the networking card itself might not have survived the trip intact, and started to look for the same Apple card that was doing such a fine job in my IIsi.

While I shopped, I did a little research on line to see if this was perhaps a well-known problem. I didn’t find anything of great interest on the topic, but this lack of information did cause me to think in a little more depth about the problem, and ultimately I vectored off into the area of link speed auto-negotiation, something I came to find out that all modern switches do, and most vintage ones did not. The reason is simplicity itself. The standard used for auto-negotiation, IEEE 802.3u (“Fast Ethernet”), was released in 1995. My non-communicative Mac IIfx was released in 1990!

The Farallon networking card was clearly also released sometime in this period, but just when was not clear. It’s documentation said that it supported IEEE 802.3, but it did not mention IEEE 802.3u. However, even if 802.3u was supported by the hardware, perhaps something was missing in the Mac OS 6.08 software layers that was being handled in firmware on the Apple networking card?

I never did answer this question, and so must leave it hanging for your consideration should you ever run into a similar bind. At this point, I took a different turn. IF auto-negotiation was the issue, this could be tested for easily by simply removing the need for it – get a 10 Mbps switch and try that. I decided to do just this, but in a “modern way”. I found an inexpensive managed switch that would allow me to manually set the speed of a link and thus eliminate auto-negotiation entirely. In this case, I chose the NetGear ProSAFE GS108PE, ordered one on Amazon and it arrived a few days later.

Netgear ProSafe GS108PE Switch (802x510)

To make a long story short, I plugged the new switch in, used its built in web interface to set the speed of one of the links to 10 Mbps Half Duplex, plugged the cable from the Mac IIfx into the selected link and it came up right away! I have been using it successfully ever since and can report that it is very stable. A whole lot of files have been transferred over the network via that switch since that day.

We can learn a few things from this exercise:

  • Some older networking cards will successfully establish a link with a modern auto-negotiating switch and some won’t. I have unearthed various reports since then indicating that various cards by Asante do quite well, as do the Apple card I mentioned above. See this link for model numbers:

I cannot vouch for the cards mentioned of course, and the article does not indicate what sort of switch these cards were tested against, so your mileage may vary.

  • If you have none of the above cards, you may wish to approach the issue of network connectivity with some patience. My experience suggests that a managed switch with the link speeds set to 10 Mbps Half Duplex may save you a great deal of grief.
  • Apple made a good networking hardware “back in the day”!

Good luck networking your older Mac!


The Mighty Macintosh IIfx

In the second half of last year, the Happy Macs lab had the good fortune to acquire a Macintosh IIfx at a reasonable price.

Mac IIfx

Regular watchers of Macintosh offerings on eBay will know that on the rare occasion when a Macintosh IIfx is made available for sale, its price is typically anything but “reasonable”. So, when the opportunity presented itself, I pounced immediately, but then the machine sat quietly in a corner of the lab for the last many months, while I completed the series on System 6, and then a new series on the SyQuest EZ-135.

Most users familiar with vintage Macintoshes will hold the Macintosh IIfx in something approaching awe, and not just because of the jaw-dropping prices that it still regularly commands. Released in March 1990, the Macintosh IIfx was at the time the fastest Macintosh ever delivered to market. It was retired in April of 1992, but it would not be outperformed in the Apple lineup until the July 1993 release of the Macintosh Quadra 840AV.

Frank Casanova, the Apple product manager for the Macintosh IIfx, dubbed it “wicked fast”, a moniker that was not only accurate, but long lived as well – in enthusiast circles, the Macintosh IIfx is still known as “the wicked fast Mac”. Frank was from Boston, a place where the adjective “wicked” is routinely used in the same sense as the word “extreme”, making sense of the “wicked fast” designation.

Wicked Fast Pin (Cropped)

The Macintosh IIfx was not just “wicked fast” however, it was also “wicked expensive” for the time (and even for today!), weighing in at $10,000 to $12,000 USD, depending on the configuration. It has been reported that some customers interpreted the “fx” designation as an acronym for “F#@*ing eXpensive”, an understandable response to this elevated price point.

What did customers get for all that money? A beast! While employing the same external case as the Macintosh II, the Macintosh IIfx was a very different animal under the skin. It was powered by a Motorola 68030 CPU running at a then blistering 40 MHz, almost twice the clock rate of the fastest Macintosh Apple had offered to that point (the IIci). Keeping that screaming fast CPU “fed and watered” was 32KB of Level 2 cache, which was not optional, as it was on the IIfx’s running mates, but rather supplied as standard equipment. Byte magazine declared the IIfx to be the new “top of the line”.

Mac IIfx Byte Cover

The performance DNA didn’t stop there either. This was a machine built for “wicked performance”. Its’ hardware included a number of proprietary ASICs that were designed to enhance the speed of the machine further, including a brand new SCSI controller, two 10 MHz 6502s (the same CPU which at 1 MHz formed the heart of the Apple II!) handling support functions and all I/O, and finally, to round things out, an ultrafast type of 64 pin SIMM RAM, with parity. The system software played its’ part too. All this highly optimized hardware required equally optimized software and as you might expect, the Macintosh IIfx required a specific version of System 6 (and later, System 7) to fully exploit it.

All this dramatically over-engineered hardware seems like incredible overkill for the typical Macintosh user of the day. What possessed Apple to field such an ultra high end machine? …a frontal assault on the engineering workstation market, or perhaps the graphic design workstation market? No one really seems to know, but a quite different thought is often reported. It is rumored that the IIfx was created under a United States government contract, which required Unix workstations with specific hardware features, and which was endowed with a generous budget. It perhaps corroborates this thought ever so slightly that Apple released version 2.0 of its’ A/UX Unix implementation at the same time as the Macintosh IIfx, and that A/UX 2.0 could be pre-installed on the IIfx’s hard drive.

It’s not clear how many Macintosh IIfx units were sold to the US government, or if any were at all, but at the time Apple was interested enough in this high-profile and high revenue market segment to later create a new business division to serve “large businesses, government, and higher education”. Apple continued development of A/UX until 1995.

Fast forwarding back to the present time, not so long ago an instance of this very machine sat expectantly in the Happy Macs lab, waiting for life to be breathed into it. It came preloaded with a minimal installation of System 7.5.5, but I reloaded it from scratch, with both System 6.0.8 and System 7.0.1. I will report on that process here in the pages of this blog.

I will also report on benchmarks between the same software and tasks running under System 6 on the lab’s 20 MHz Macintosh IIsi and then on the 40 MHz Macintosh IIfx. The delta should be illuminating. Finally, I will be reporting on benchmarks between the same software and tasks running under System 7 on the lab’s 68040-equipped Quadra 660AV and on the 68030-based Macintosh IIfx. I had an expectation that the Quadra’s 25 MHz 68040 would perform at similar levels to the IIfx’s 40 MHz 68030 when both were running System 7. The results should provide an interesting glimpse into the relative performance of these two CPUs.

Until next time!

Return to Snow Leopard

Occasionally, in the pages of this blog I post about things that are not of and by themselves directly about vintage Macintoshes, but which are related in some way to vintage Macintoshes. This is one such post, and concerns itself with Mac OS X Snow Leopard.

Mac OS X Snow Leopard

Snow Leopard has always been one of my favorite releases of Mac OS X. It was a rare big cat indeed: a release largely dedicated to stability and performance instead of flashy new features. Snow Leopard was a move that only Steve Jobs, with his commanding technical and market authority, could have pulled off successfully. It was also, IMHO, the last “true” release of Mac OS X, before the creeping IOS’ification of Mac OS X began with Lion. My only real issue with Snow Leopard was (and still is) that it did not support the Power Mac G5, forever stranding my 2.3 GHz G5 Dual at Leopard, and in practical daily usage, Tiger, which has always been a favorite as well.

Released in 2009, Snow Leopard is now ten years old, and at that age, it almost qualifies for discussion in a blog dedicated to vintage Macs. However, this blog is dedicated to pre-Intel vintage Macs, and so technically Snow Leopard is out of scope no matter what its’ age. However, I am going to relax that restriction for this one post.

Why think about Snow Leopard now? Well, since 2011, my daily driver has been an early 2011 27” iMac, running Mac OS X Mavericks these days (I had to upgrade it from the Mac OS X Lion it came with in order to add a USB3 dock). My iMac has been in every way a satisfactory machine, and with a large and speedy SSD as its main boot drive, it has been very fast as well. However, the machine has slowly been losing that cutting-edge speed, and after eight years of faithful service, I had begun to think that a complete reload might be the best cure.

2012 iMac

However, that got me considering whether it might not be time for an even bigger change… reinvigorating my long idled 2008 Mac Pro, loading it with Snow Leopard (it still ran the Leopard that it came with) and going “back to the future”. The more I thought about it, the more I liked the idea of a sleek, optimized and at this point almost iconic version of Mac OS X as my main operating environment.

2011 Mac Pro (442x640)

SO… I have taken the plunge. I have reloaded my Mac Pro with Snow Leopard and have moved onto it full time. My Mac Pro is a beefy machine, and loaded with Snow Leopard, it really flies. The only restriction I have found so far is that there is absolutely no completely current web browser for it, which has had the practical side effect of requiring me to fire up my iMac whenever I need to access my bank, whose web site insistently requires that it only be accessed by the most current technology. Other than that, all is well in Snow Leopard land.

Perhaps I should say that all is better than well. Snow Leopard comes with a number of advantages for vintage Mac enthusiasts. Perhaps the most compelling of these is that it is the last release of Mac OS X to sport Rosetta PowerPC support, enabling access to my full arsenal of PowerPC programs, many of which did not make the transition to Intel. In case this has you thinking about it, no, Snow Leopard does not support the old Classic environment, so you cannot run those truly venerable Mac OS programs.

All in all, I am very happy with my new daily driver, and really enjoy the speed, stability and enhanced program set that it enables. Now I know that some purists out there will take exception to this move backwards, but please hold your fire. I fully agree that Snow Leopard is not as secure as Apple’s most recent macOS offers, but I practice safe computing, sit behind a substantial firewall and have experienced no issues whatsoever.

Looking ahead, it has been rather quiet here at the Happy Macs blog for the majority of 2019. This is not because I have not been busy with vintage Mac projects, but rather because some of them have been sizeable, and have taken quite a long time to complete. This, coupled with a demanding job, and a newly enlarged commute (which eats up far too much free time each day!) has slowed things down rather more than I would like. However, with several projects now complete, I am ready to start posting, and you should be seeing a small flurry of posts over the Christmas break.

In those posts, we will be delving into the Macintosh IIfx, Apple’s foray into Unix (A/UX) and even some new software that I have developed for the A/UX environment, which I will be adding to the Happy Macs Gopher site. Stay tuned!

Recommended Links Updated

Every now and then I like to check up on the links on my Recommended page to ensure that they are all still “live”. I am pleased to report that all links seem to be in good health.

While I was there checking through the links, I took the opportunity to update the list with some new entries that you may wish to look into. The vintage Apple community is alive and well! Here are my latest finds:

  • Resto-Bytes, a blog written by my fellow enthusiast Ty, who is doing great work restoring vintage Macintosh computers, sometimes one chip at a time! Resto-Bytes is well written, very detailed, and provides lots of practical advice along the way, coupled with real-life photos of work in progress. It is well worth a trip over.
  • r/VintageApple, a Reddit blog which says that it is about all things vintage Apple. As you might expect from a Reddit based blog, r/VintageApple is graphics-heavy, which makes it an enjoyable browse. Head on over and check it out.
  • ThinkClassic, a set of forums devoted to all classic Apple computers, not just the Macintosh. As such, you will find areas for the Apple I, II and III, for the Lisa and many, many more products. Unlike many vintage computer forums, ThinkClassic seems to be fairly active. You many find it valuable to become a member.

That’s it for this update!


The SyQuest EZ-135 and System 6

At this point in our series on the SyQuest EZ-135, we have looked at the history and market results of the product, have installed it onto a Mac OS 8.6 Power Macintosh 7500/366 and run performance benchmarks between the EZ-135 and its primary competitor of the day, the Iomega Zip-100. However, with all the work this blog has done recently on System 6, I could not leave the EZ-135 topic without seeing how it would perform under System 6.

The EZ-135 retail box (see below) states that support is provided from System 6.0.5 onwards, and so the game was on. This post examines how well that support really works on a real world System 6 machine, the Happy Macs lab Macintosh IIsi.

EZ-135 Retail Box Back

The Software:

As with the initial Mac OS 8.6 testing of the EZ-135, the first thing to do was to install the software. You will recall from the earlier posts in this series that this was a set of three files (vs. the dozens provided for Windows!). I copied these files over to the IIsi and gave them a whirl.

This was a minimal experience on System 6. The utility crashed the machine, necessitating a restart to recover control. The “readme” file… wouldn’t let me! It too crashed the machine. Finally, but happily, the SilverLining Lite utility did run. Following my nose, and knowing that it was a control panel, I copied it to the System folder and restarted the Mac.

After a successful boot sequence, SilverLining Lite did show up in the Control Panel DA as expected.

The Hardware:

I powered down, plugged in the EZ-135 (ironically, I connected it to the middle of an external SCSI chain that was terminated by an Iomega Zip-100!) and rebooted once again.


As you can see below, the SilverLining Lite control panel recognized the new comer to the chain and displayed it at SCSI ID 5:



I inserted a cartridge, slid the Load/Unload lever all the way to the right, and waited expectantly for the disk to mount on the desktop. After the cartridge was obviously fully spun up, and no more accesses were occurring, it became clear that it simply WASN’T going to mount on the desktop. Now at this point I recall reading a review from the period that indicated that cartridges had to be manually mounted and unmounted, so I went hunting for a way to do that. Ta Da! The SilverLining Lite control panel had “Mount” and “Unmount” buttons, so I pressed the Mount button and that did the trick – the cartridge mounted on the desktop right away.

Desktop w EZ-135

After this one additional step (manually mounting the cartridge), I was able to use the cartridge as normal, copying files onto and off of it with no issues. When I had satisfied myself that the drive and cartridge were working fully, I tried to unmount the cartridge by dragging its icon to the trash. No joy! The icon would in fact disappear, but then immediately reappear on the desktop.

I rather expected that something like this would happen. If the cartridge had to be manually mounted, it probably had to be manually dismounted too, but I had to push my luck and see if simply dragging the icon to the trash would accomplish the goal. Clearly it would not, so I pulled up the SilverLining Lite control panel again and pressed the Unmount button. I am sure that you will not be surprised to read that the cartridge obediently and immediately spun down and ejected.


So far, so good. Using the EZ-135 under System 6 required 2 more steps (manual mount, manual unmount) than using it under Mac OS 8.6, but it was still very usable and still quite intuitive.

Now that everything was clearly installed and working, how reliable was it? To find out, I restarted the Macintosh and tried everything again. This was a fortuitous step because this time, and every time since then, when I inserted a cartridge into the drive and slid the Load/Unload lever all the way to the right, the cartridge spun up and auto mounted on the desktop, without the need to use the Mount button! Likewise, when I drug the cartridge icon to the trash, the cartridge spun down and ejected, again all without the use of the Unmount button!

Thus, after the first restart, operation of the EZ-135 under System 6 (well, System 6.0.7 anyway) followed exactly the floppy paradigm, and was identical to the way the Zip-100 on the Mac IIsi also behaved. I concluded that we are “good to go” for use of the EZ-135 on System 6.

Some Closing EZ-135 Thoughts

One final note. I had not found any images of the EZ-135 retail box when I wrote the first post in this series, and in that post I wondered “out loud” whether the original retail packaging had included a SCSI terminator. I subsequently did find the image shown above, and it makes it clear that a SCSI terminator WAS included with each package. A curious choice, but one I wanted to record, so as to set the record straight.

So, there you have it. The EZ-135 story is now complete from the perspective of this blog. It runs well on System 6, and equally well on Mac OS X 8.6 (I am going to assume that System 7 therefore would support it cleanly as well), offers more capacity and higher speed operation. I am pleased to have stumbled across this useful device and I will be putting it to good use in the future!

What’s Next?

What’s coming next to the pages of this blog? Next up is configuring, loading and getting online a Macintosh IIfx that I picked up some months ago, along with getting it to dual boot System 6 and System 7. This will be followed by a long overdue segue into the interesting and wonderful world of the Apple IIGS, a sort of Apple II / Macintosh hybrid. Stay tuned… lots of fun to come!



Performance Results – SyQuest EZ-135 vs. Iomega Zip-100

In the last two posts on the topic of the SyQuest EZ-135 “super floppy”, we looked more closely into the product, compared it to the Zip-100, installed the software and hardware and got it fully functioning under Mac OS 8.6 on the Happy Mac Lab’s Power Macintosh 7500/366.

Now, with our SyQuest EZ-135 installed, set up and running successfully, the next questions are clearly “how fast is?” and “how fast is it relative to its Iomega Zip-100 competitor?”. This post delves into that question and provides answers.

The EZ-135 specs seem to have it running about 70% faster than a Zip-100, so it was time to test this out. As a quick refresher from the original post in this series, here is what the relevant specs say:

Iomega Zip-100:

  • Average Seek Time: 30ms
  • Sustained Transfer Rate: up to 1.4 MB/s

SyQuest EZ-135:

  • Average Seek Time: 13.5ms
  • Sustained Transfer Rate: up to 2.4 MB/s

As it happens, I have the good fortune to have both the EZ-135 and a Zip-100 in the Happy Macs lab, both external SCSI interfaced units. In turn therefore I connected each to the same Mac, my Power Mac 7500/366, and tested their performance at the same real world tasks.

ez-135, zip-100 test environment

The Test

The real world test tasks chosen were a small simulation of a backup and a restore: copying roughly 6.3 MB of large files (400KB to 500KB each) onto the cartridge from the HD, and then copying them back onto the HD from the cartridge. As a bonus, and since I had one handy, I performed this same “benchmark” using an Iomega Jaz 1GB as well.

The Results [drum roll please…]

Here are the results (smaller results are better):

peformance result table

These results show that in the real world work of backing up and restoring files, the EZ-135 is faster than the Zip-100, but not by quite as much as the above specifications might lead you to expect. The EZ-135 was 33.9% faster to copy from the HDD to the cartridge, and 41.5% faster to copy from the cartridge to the HDD. Of course, the Jaz drive outpaced both of them by a healthy margin, which comes as no surprise.

SyQuest EZ-135, Conclusions and Wrap Up

In head-to-head performance testing, the EZ-135 beat the Zip-100 by at least 33%, and up to as much as 41%, at the primary task which framed their all too brief time in the sun – backup and restore. Setting these results aside for just a moment and looking at the rest of the commercial offer, the two platforms were remarkably similar: both featured solid hardware platforms, good to excellent software support and very similar usage paradigms. So, with all other things being more or less equal, and with its higher performance, why didn’t the technically superior EZ-135 dominate the market? What happened?

In the end, it may be as simple as time-to-market. The Zip-100 had a six month market lead on the EZ-135, and was firmly established before the EZ-135 debuted. In addition, it was backed by aggressive marketing, widespread bundling with manufacturer offerings (Apple offered the Zip-100 as an option on several models of Macintosh, as did many PC vendors) and a slightly lower price point. Thinking back, I purchased a Zip-100 almost as soon as they came out, and I remember being dimly aware that there was now a competitor when I decided to purchase a second one. However, cartridge compatibility was important at that point, and my second “super floppy” (and all subsequent ones until this series of blog posts) was another Zip-100.

That may be it in the final analysis… time to market and cartridge compatibility. We will never know of course, and so the EZ-135 remains as a fascinating “what if” product, but one that I have been pleased to bring back to life in the pages of this blog, if only for a brief moment.

On a personal note, as a result of this series of posts, I now have two of these excellent devices in the lab, and I plan to keep them in service doing the type of work they shine at these days… mass file transfer to vintage Macintosh computers that I am performing initial software loads on. Of course, the Zip family of devices is well represented throughout the Happy Macs lab and is not going away, and so both the EZ-135 and the Zip-100/250 will coexist and each be used as the application of the moment dictates.

This might seem like the end of the road for this series of posts but we are not quite there yet. There will be one more post… After all the work I have done recently on System 6, I couldn’t resist testing the EZ-135’s support on System 6 Macs. This is particularly useful to me just now as I have a newly acquired Macintosh IIfx that I am about to load up with System 6 and a set of compatible applications. Stay tuned therefore for one last edition of the “EZ-135 story”, telling the tale of System 6 and the EZ-135. Coming soon to a blog near you! Until then…