G4 Power Mac

Yikes!

This is the code name Apple gave their first ever G4 Power Mac. One of these Macintosh computers this article is about. Technically almost identical to a Power Macintosh G3 (Blue and White) but with a Motorola MPC 7400 on the logic board – better know as G4 processor – this Power Mac debuted the pro-line graphite case in 1999. Initially this role was meant for a brand new Power Mac with AGP graphics instead but Apple was not able to get the new Mac ready in time.

Why resurrect an old Mac?

I am quite fond of this model for various reasons: we used Macs like this one back at university, it was my first hands-on experience with Macintosh computers and Mac OS 9, and it is a design icon. Furthermore I have a number of old documents which depend on applications from the Classic Mac OS era and I would like to have a Mac which supports hardware and software from around the year 2000. This computer can run both, Mac OS from 8.6 up to 9.2.2 and Mac OS X up to Tiger (10.4).

I got my used 400 MHz Power Mac a couple of years after this model was introduced. Generally in good nick it already showed some battle scars: a few scuff marks and scratches on the outside and a tendency to hang or crash while doing some heavy lifting. Larger software installs, for example, were taxing one's patience.

3, 2, 1, Ignition

After a very thorough inspection which involved disassembly and cleaning I got ready to start up the Power Mac for the first time after more than a decade. Power cable, display, Apple Magic Keyboard and Pro Mouse were connected. Would it work? Would it successfully start up an operating system? I pushed the power switch.

I was immediately reminded that the concept of a noiseless computer was not a thing in 2000. Loudest of all was the internal hard drive, a very reliable but constantly buzzing 16 GB IBM drive. A while and some screen flickering later Mac OS X Tiger's desktop came up. It worked!

Well, of course there were a few minor issues: due to the Mac's long slumber the real time clock's battery was flat and the computer back in 1970 – nothing that cannot be fixed with a new battery or access to a time server. Also I noticed that startup commands did not seem to work with the modern Magic keyboard. It turns out that this particular model did not come with the new Startup Manager later G4s have and therefore I was in fact using the wrong commands. If you want to hold the ALT key (known as Option key nowadays) to be presented with a choice of boot devices during startup you will have to get a G4 Power Mac with AGP graphics or newer. However C and D keys for starting from CD or internal hard drive worked.

Hardware Upgrades

Hard Drive Replacement

In order to turn this Mac into a (more) quiet computer the internal IDE hard drive had to go. No worries, I did not throw it away. SSDs can be used with IDE-SATA adapters on IDE controllers. Cheaper and easier to use are adapters for Compact Flash or SD cards. Easier because you can simply take out a card and partition it or copy files onto it with most modern computers. I ended up buying an IDE-to-SD adapter and a 32 GB SD card. Using an external USB to SATA/IDE adapter I cloned the old hard drive to the SD card with dd on a more recent Mac. Both Driver Descriptor Map and the last free partition entry of the Apple Partition Map were adjusted to the new disk size with HexEdit. With that taken care of I connected the SD adapter to my Power Mac's IDE cable which was used with the original hard drive previously.

Each time after the OS search I was presented a white screen showing a grey apple logo and the spinning load animation: the Mac OS X startup screen. So far, so good. But to my surprise this Mac behaved somewhat erratic. While sometimes it would start to desktop, it often would instead replace the apple by a no-sign and then stop there. Once I even ended up in a root shell in which I poked around a bit: I noticed that while I could list directories on Macintosh HD, quite often I would get a bus error message when repeatedly listing directories. If data on the volume was corrupt then I would expect errors to occur consistently. Something strange was afoot.

I checked the adapter – no jumpers. Therefore a configuration problem at this end was more than unlikely. The adapter was the only drive attached to this IDE port on the logic board which ruled out a bus conflict. Installing Mac OS X onto the SD card from the optical drive either failed with varying progress or showed the same symptoms after restart. I noticed that the port to which the DVD drive was connected was labelled IDE on the logic board, while the other one for hard drives (which I had been using) as Ultra ATA. Did the SD adapter not support ATA/33? Was the ATA onboard controller or its port faulty?

There was one easy way to find out. I connected the SD card adapter to the same port as the DVD drive, jumpered the DVD drive to slave mode and started up my Mac from DVD again: Partition SD card and verify: check. Install Mac OS X Tiger: check. Restart from SD card: check. This machine started to feel like a real Mac after all. Even after several restarts and hours of use these issues did not surface again. With an entirely silent boot device and a transfer rate just under 15 MB/s as result I consider this a successful upgrade and fix.

Memory

Now that this Power Mac is back in service there is a bunch of things I would like to improve. In order to further optimise performance I am planning on upgrading this machine's memory to 1 GB. This model has four DIMM slots which support 256 MB PC100 SDRAM modules. When I got this machine out of storage it had two different 128 MB DIMMs (one with Mitsubishi ICs) and one 64 MB DIMM (apparently by Hyundai) installed. As PC100 RAM is getting harder to acquire I got a promising PC133 RAM module instead, which works fine with this logic board: I ran two benchmarks as stress tests and did not witness anything out of the ordinary. The PC133 module does not work with any of the older PC100 modules though, which means this Mac now has a whopping total of 256 MB of RAM until the other three modules arrive – hopefully soon.

Case Fan

Apple's internal 120 mm case fan I replaced with a modern low noise case fan of the same size. To power the fan Apple used a connector which does not meet today's standards. I salvaged the old fan's cable to build an adapter. The fan worked perfectly and the reduction of noise was quite noticeable.

Future upgrades

As per design the internal case fan runs constantly. It would be nice to add a PWM speed controller of some sort in order to reduce noise further.

While the PC-world had moved on to USB 2 Apple still integrated version 1. Mostly as a drop-in replacement for the Apple Desktop Bus (ADB) to connect keyboards and mice. More oomph in form of USB 2 would be desirable. I read about all-in-one cards with USB 2, Firewire and IDE controller for this type of Mac – like the Sonnet Tempo Trio. I would like to get one of these, especially since the Mac's built-in Ultra ATA does not seem to work correctly. Another reasonable addition would be a SCSI controller for period-correct peripherals: external storage solutions from SyQuest or Iomega, for example.

I am wondering whether a PC Compatibility Card could be convinced to work with this Power Mac. This is a rather exotic expansion card developed for the earlier Power Macintosh computers and whether this is an upgrade or not is debatable. But wouldn't it be hilarious to run DOS or even Windows 98SE on a dedicated Pentium 166 MHz inside a Mac? This could be a quite exciting project on its own. However, such cards are very rare nowadays.

Conclusion

There is another Power Mac brought back to life and it looks great. I am looking forward to exploring vintage software and excavating long forgotten treasures from old backups with it.

With Mac OS X it was relatively easy to integrate this machine into the local network (it even supports IPv6). Screen sharing from macOS Catalina worked just fine. However, the out-of-the-box file sharing support is outdated. Modern Macs default to modern Windows file sharing and that means authentification methods Tiger does not know. Instead I used an older version of sshfs to connect to shared files on other machines. For later a Netatalk-Server might be the right thing to set up, one that speaks Apple Filing Protocol (AFP), which both, Mac OS and Mac OS X, can handle natively.

Trying to surf online however was abysmal. With the introduction of HTML5 around 2010 and widespread use of modern encryption nowadays browsers native to PowerPC-based Macs are now severely outdated – to a point where in most cases they cannot and in general should not be used. TenFourFox looks like one very promising modern browser for Power Macs of today and I will test it as soon as the G4 has more memory.

A rather positive surprise was that Software Update still receives updates from Apple servers and was able to update Mac OS X to the latest version (10.4.11, build 8S165). Thank you Apple for still supporting Power Macs from the last millennium!

Seeing this Power Mac output Full HD was unexpected as well. System Profiler claims the ATI Rage 128 outputs at 60Hz and a colour deph of 32 bits (known as Millions of colours which actually boils down to True Color or 24-bit RGB). Not too shabby and not that retro at all.

Although it is theoretically possible that the SD-adapter and the Power Mac's Ultra ATA controller are somehow incompatible I think it is much more likely that there is a defect on the Mac's side, given that there always have been stability issues especially when installing software to a drive connected to that controller. I would love to get more information about the onboard controller. My ongoing online research has not revealed anything substantial yet.

That it is getting increasingly harder to find certain replacement parts or upgrades for a 20 years old computer, does not come as a surprise. But I was shocked about the sheer amount of dead links I came across during researching related topics and product documentation online. True, Apple has restructured a majority of their online available product and developer documentation during the last years, which has quite an impact on many other websites, but sadly entire personal and commercial websites have disappeared from the web and with them well curated content and a lot of knowledge. The internet does forget! All hope lies in the fan-driven online archiving projects, head-on facing the challenge of preserving information and software alike.

Hardware Summary

Interestingly Mac OS X Tiger displays Power Mac G3 (PCI graphics) in System Profiler while Mac OS 9 gets the machine name right. For the ones who are interested in more technical details or want to compare to their hardware I added the Power Mac's specifications.

• Machine Name
  Power Mac G4 (PCI graphics)
• Machine Model
  PowerMac1,2
• CPU Type
  PowerPC 7400 v2.6 (G4)
• CPU Speed
  400 MHz
• L2 Cache
  1 MB
• Bus Speed
  100 MHz
• Boot ROM Version
  1.1.2f2

Also the components I used and which worked for me are listed below. I am, of course, not affiliated to any of the vendors and mentioning these products is for informational purposes only and constitutes neither an endorsement nor a recommendation.

• SD Card adapter
  Kalea Informatique Adaptor IDE 3.5-inch 40 Pin to SD Card
• SD Card
  SanDisk Ultra 32 GB SDHC
• RAM
  Mushkin Enhanced Essentials 256 MB 168-Pin SDRAM PC 133 (990614)
• Case Fan
  Arctic F12
• IDE cable
  Tutoy 40 Pin PATA/IDE 3.5-inch Male To Female Ribbon Cable
• VGA-to-HDMI
  Gana VGA to HDMI Converter Adapter
• Wireless-to-Ethernet
  Apple AirPort Express 802.11n (2nd Generation)