Follow Up on the 6100, 7100, and 8100

- 2000.04.06

I got such a large response to my article Picking an Older Power Mac that I decided to write a follow-up. Thanks to several people, especially Paul Linblad, for pointing out that the Power Macintosh 6100 actually uses up to 640 KB of DRAM for video, not 1 MB as I had mentioned earlier, and that it is possible to install a G3 upgrade as well as another video card. This adapter, however, does cost $100, and you cannot put any other NuBus or PDS cards into it. This is usually a good option if you already have a 6100 or are able to obtain one for a very low price.

However, if you spend the extra $75-100 for a 7100, you will get better performance, as well as more NuBus slots, a better internal speaker, an extra 5.25" drive bay (if there is no CD-ROM installed), and soft power. If you spend another $100 for an 8100, you will get better performance yet, as well as two extra drive bays (one if there is a CD-ROM installed), plus the advantage of a tower case, which can be put under the your desk to save space.

Anyway, there are a number of upgrade cards available for the 6100, 7100 and 8100 series computers. It is nice to have a computer that can be upgraded to a G3 or better, but don't buy it just because it can be upgraded. Make sure it is a system you'll enjoy using. If you expect to buy a new computer in 2 years, consider looking at a machine with a little less upgrade capacity, because you will be less likely to use them, and you can often save a lot of money by buying a computer with fewer upgrade options.

If you need more speed, look at cards such as the Newer Technologies MAXpowr G3 PDS with 1 MB of level 2 cache. Depending on your machine's bus speed,* you can run the MAXpowr G3 at up to 300 MHz!

* The original G3 processor can run at up to eight times bus speed, which ranges from 30 to 40 MHz on the x100 models as follows: 6100/60 = 30 MHz; 6100/66, 7100/66, and 8100/100 = 33 MHz; 7100/80 and 8100/80 = 40 MHz; 8100/110 = 36.6 MHz. Newer G3s can run at ten times bus speed. This limits performance to 240 or 300 MHz on the 6100/60, 266 or 333 MHz on the 66 and 100 MHz models, 320 or 400 MHz on the 8100/80, and 293 or 366 MHz on the 8100/100. The G4 is currently limited to nine times bus speed.

Other major cards include the Sonnet Technologies Crescendo series of cards. These are the Crescendo G3 240-266 MHz with 512 KB cache, G3 240-266 MHz with 1 MB cache, G3 300 MHz with 1 MB cache, G3 400 MHz with 1 MB cache, and the newly released G4 (yes, G4!) 360 MHz with 1 MB cache. The 400 MHz G3 card only runs at 400 MHz in the 80 MHz Power Macs, and the 360 MHz G4 card only runs at 360 MHz in the same machines. The rest of the G3 cards run at ten times bus speed in all other Macs, and the G4 card runs at nine times bus speed in all other Macs.

Before you rush out and buy a nice new G4 card, remember that a lot of new USB and FireWire peripherals will not work on your newly upgraded machine. If you plan to use new USB or FireWire devices, consider buying a new computer, or a second hand or refurbished Power Macintosh G3 Yosemite (the blue and white model) - or another Mac OS computer with PCI slots that can accept USB and FireWire cards.

Another thing to think about when buying a used computer is what kind of monitor to buy. I won't cover this in detail, but I do recommend looking at more than one brand of monitor. In terms of monitor size, I recommend no less than 15" on your main computer, and no less than 13" on a second computer.

When I bought my Power Macintosh 8100, I wanted to get a matching Apple monitor. I looked at three: an AppleVision 1710, a Multiple Scan 1705, and an AudioVision 14. I decided the picture was bad on the 1710, the price was too high on the 1705, and the screen was too small on the AudioVision. I was about to spend almost $200 on the 1705 display when I saw a nice 17" NEC monitor for over $100 less. I took one look at the picture, knew it was better, and bought it without hesitation. I saved almost $150 with that decision.

Sure, It is nice to have an Apple computer, an Apple monitor, and an Apple keyboard and mouse, but you can often save a lot of money by compromising and getting a keyboard, mouse, or monitor made by a different company. That is money you can use to buy more memory or a bigger hard disk for your new computer.

Further Reading

• Profile: Power Mac 6100 (a.k.a. Performa 61XX)
• Profile: Power Mac 7100
• Profile: Power Mac 8100

Adam Robert Guha was brought up on a Mac Plus, tested on a Performa 5215 CD, and fine tuned on a Power Mac G3/233 DT. He has worked with the Mac II series, as well as LCs and early Power Macs, such as the 6100. He currently own several 68030 machines, including some interesting models like the Colour Classic. At school, many of the Mac-owning teachers ask him for assistance. He has upgraded and reinstalled software on 15 computers at school - and counting (mostly late 68K Macs and early Power Macs).