The Mystery of the Missing Content

Reader DaveC pointed out that I left you folks hanging with my 9150 reference last month. I had originally meant to elaborate more on that at the time, but apparently my subconscious was looking ahead to this month, and provided me with material for an article.

What’s so great about the 9150, you ask? Sharing a case with the Quadra 900 series, but with a unique faceplate, the 9150 has a PPC PDS (shared with the other x100-series Power Macs), four NuBus slots, a DB-15 video connector (the only Mac in the x100-series with this feature), eight 72-pin RAM slots, twin SCSI buses (the internal is 10MBps Fast SCSI-2, while the external is the standard 5 MBps SCSI-2 present on other Macs) and support for up to eight drives mounted internally. Yep, eight—a floppy (mounted 2/3 of the way down the front, thus the unique faceplate), an HP tape drive, a CD-ROM, and five internal hard disks. Getting the side panel back on after installing such a setup is quite a task because of the many folds in the monstrous internal SCSI cable.

The 9150 is, like any other NuBus Power Mac, G3- or G4-upgradeable. If you’re planning on getting one to do this, however, don’t spend extra on a 120 MHz model, since both the 80 MHz and 120 MHz versions share a 40 MHz system bus, limiting maximum CPU speed to 400 MHz for the G3 (max. 10x multiplier) and 375 MHz for the G4 (max 9.5x multiplier). The only other “drawback,” if you see it as such, is that the 9150 doesn’t appear to support any SIMMs larger than 32 MB; in testing several variants of 64 MB 72-pin SIMMs in mine, I always got the message on startup:

“The built-in memory test has detected an error.”

However, eight 32 MB SIMMs are reasonably inexpensive, and they give this box a RAM ceiling of 264 MB, which is plenty for most applications under any Mac OS that runs on the box (anywhere from 7.1.2 to 9.1 for the 80 MHz model or 7.5.1 to 9.1 for the 120 MHz model).

With five internal drives, my 9150 has turned into my legacy hardware test platform and part-time LAN server. It’s a great machine to test NuBus cards in with its easily accessible NuBus slots (much more so than the 8100 or 7100). Its DB-15 video port means no irritating (and expensive) HDI-45 adapters. The five internal drives gave me nearly 10 GB of scrounged-up disk space and plenty of room to install every Mac OS variant that runs on the machine for a wide variety of test situations. Finally, it’s now running my CD burner and serving as my main backup machine with its 2 GB tape drive. They don’t get much more versatile than that, folks.

Tip of the Month

Last month’s tip on keeping the Mac plugged in to save the PRAM battery has apparently saved one British reader of this column £100 annually:

“I have a Power Mac 5500/275 and ever since I’ve had it, it’s eaten batteries—every three months it’s said ‘Date and time need resetting’ and has asked for a new battery. At 25 pounds sterling a time…Just last week it did it again…then I read your tip and I thought, ‘It won’t work but it’s worth a try.’ So I switched the Mac off but didn’t switch it off at the plug. Next time I switched on—no problem!”

That’s a pretty strong testimonial. Keep those babies plugged in unless you want to be spending lots in annual maintenance.

His letter, however, brings up another topic: where to get those batteries, which often cost an arm and a leg, as the reader notes (£25 is about US$34 for the American readers). I’ve had good luck with All Electronics for the standard 3.6V 1/2AA batteries, where they have 5-year-old new stock batteries for $1.50 each, or $1 each in bulk. Lithium batteries have a 10-year shelf life, and I’ve had no problems with the batteries I’ve gotten from All Electronics so far. Even if one in ten is dead, it beats paying $11 each at my local Radio Shack. Other World Computing is the best source I’ve found for the cube-like black Rayovac 841 4.5V alkaline PRAM batteries used in most Macs that don’t take the 3.6V 1/2AA. At $9 each, they’re substantially more expensive, but again, Radio Shack charges nearly twice as much and they have to special order it in many cases. For the Mac Plus and earlier, the necessary Eveready 523 (a 4.5V AA-size battery; note that a normal AA will not work in most cases) can be obtained via special order through Radio Shack for about $8. A big thank-you goes out to the pickle’s Low-End Mac FAQ for providing sources for the batteries.

Once you have the battery, the Mac Battery Web Page will be quite helpful in figuring out how to replace the old one. For the hardware hacker types, the 4.5V batteries can be replaced with a 3-AA holder and some creative wiring, giving you a battery that will last at least as long but costs only $1.50-2 to replace (the cost of three AA cells). I got my 3-AA holder from Digi-Key for about $2.50 and scavenged the wiring and plug from a dead Rayovac 841.

Trivia Answers

A1: The LaserWriter IINT (Leia), IINTX (Darth Vader), and PowerBook 150 (Jedi) were the three pieces of Mac hardware. If you really want to stretch, the LaserWriter IIsc (Solo) might be the fourth one here, but “Solo” is too ambiguous to say for certain. Bonus answer: the Apple IIc had “Yoda” among its 13 code names.

A2: Lisa, Macintosh, and Newton were all original project code names.

Thanks to MacKiDo for the information on which this month’s trivia is based.