In the beginning, the Mac had been conceived as a closed box, an information appliance with no option for internal upgrades. The first two models had no expansion slots, no high speed bus for a hard drive, and no memory upgrade path, although a lot of Macintosh 128K owners learned how to upgrade to 512 KB of RAM.
There were also some third-party upgrades, including memory expansion beyond 512 KB, faster CPUs (I believe 12 MHz was the fastest), and internal hard drives. Apple’s first hard drive used the Mac’s slow floppy drive port.
The third Mac, the Macintosh Plus, looked like the earlier Macs, but there were several internal and external changes. The biggest improvement was memory: The Mac Plus shipped with 1 MB of RAM and could be upgraded as far as 4 MB. It was the first Mac to support internal upgrades.
The Plus was also the first Mac to use SCSI for external expansion. The SCSI bus supported hard drives, scanners, tape drives, and other external devices. It was also significantly faster than the floppy drive port.
Apple also switched from DB-9 serial ports to mini DIN-8 serial ports, which would remain in use until USB began to replace it with the iMac in 1998. (It was also in the iMac era that Apple was phasing out support of SCSI.)
The Mac Plus introduced a new keyboard with a numeric keypad and arrow keys, which earlier Mac keyboards didn’t have. The arrow keys helped reduced mouse dependence.
Introduced on March 2, 1987, the Macintosh SE appears to be a visual redesign on the original Mac design. The compact Mac form factor was the way Macs were supposed to look (and part of the reason Low End Mac’s logo used to look like a compact Mac); the changes were hidden to the casual viewer.
From a practical standpoint, the SE’s biggest improvement was a second internal drive bay, which could hold a second floppy or – something new from Apple – an internal SCSI hard drive. It was a pretty pathetic 20 MB MiniScribe drive. (If you have an SE, consider replacing the hard drive with almost any half-height 3.5″ SCSI drive built since 1989, about the same time manufacturers started putting buffers in hard drives. Old LCs can be a great source of 40 MB drives to transplant into the SE.)
Although it’s hard to imagine a practical reason to do so, you can install a multi-gigabyte hard drive. Apple’s HD SC Setup lets you create up to eight partitions of up to 2 GB each. Yes, that’s probably overkill for an SE, but it’s an indication how future-oriented the Mac hardware and OS were in 1987.
SCSI had been improved since the Mac Plus was introduced, and the SE supports throughput of up to 5 Mbps – a huge improvement over the 2.1 Mbps maximum of the Plus. In real world benchmarks using the same 160 GB Quantum hard drive with a buffer, the SE’s throughput measures about 2/3 faster.
You can think of the SE’s SCSI throughput as about half the speed of USB 1.1, which is very slow by modern standards. Still, it was pretty impressive compared with the Plus.
On the back are a pair of ADB ports, supporting the Apple Desktop Bus introduced the previous year on the Apple IIGS. Although used primarily for mice and keyboards, ADB also supports sketch tablets, a few slow modems, and not much else. ADB remained a feature of all Macs until the iMac replaced it with USB in 1998.
The most revolutionary change in the SE was inside the box – an expansion slot. This was Apple’s acknowledgment that the concept of a closed, unexpandable information appliance was too limiting for its customers. The SE PDS (processor direct slot) gives the SE the ability to add features Apple hadn’t built into the computer, such as support for an external portrait display, a DOS card, or a high speed network card (ethernet was relatively unknown on personal computers in the 1980s).
If the SE subtly broke the Mac mold, the Macintosh II blew it to pieces. There was no internal monitor. It didn’t have a small footprint. It wasn’t portable. It looked like a business computer, although it was far more attractive than the plethora of DOS boxes then on the market.
Going way beyond the SE, the Mac II has room for two internal floppy drives and a half-height 5.25″ hard drive. Instead of a single proprietary expansion slot, Apple adopted the emerging NuBus standard and included six expansion slots in the Mac II.
As with the original IBM PC and the pre-2013 Mac Pro, at least one expansion slot has to hold a video card. But unlike most computers of the era, each of the NuBus slots could hold a video card, and the Mac OS would let the user decide how they were connected into one giant, screen-spanning desktop.
With the Mac II, the black & white Mac gave birth to color. With Apple’s color card, the Mac II could display 8-bit color at 640 x 480 resolution – 256 colors from a 16 million color palette. Later in life, it would also be able to support 24-bit and 16-bit video cards. (At about the same time, IBM introduced VGA, which supported 256 colors at 320 x 200 or 16 colors at 640 x 480. The Mac was well ahead of the DOS world when it came to graphics.)
All of this required more horsepower and more memory than earlier Macs had. The 8 MHz 68000 CPU found in all previous Macs gave way to a 16 MHz 68020, and the base 1 MB of memory on the Plus and SE was increased to 2 MB on the Mac II. Although the Mac II was intended to support up to 128 MB of memory, memory standards took an unexpected turn, so the special 4 MB and 16 MB PAL SIMMs needed to bring the Mac II beyond 8 MB (eight 1 MB SIMMs) remained expensive.
Further, until System 7 (1991), the Mac OS only supported up to 8 MB. The Mac II also had problems with “dirty” ROMs if you wanted to use 32-bit addressing (the part of System 7 that lets it use more than 8 MB of RAM). In the end, the Mac II can support up to 68 MB with System 7.x and some modifications.
The Mac II was a real workhorse. Between the more powerful CPU and higher processor speed, it has about 2.4 times the power of the SE. It can easily handle 8 MB of RAM – twice as much as earlier Macs. And that 8-bit color was stunning in the era of 64-color EGA on the PC side of things, not to mention the hot new VGA that IBM was introducing at about the same time.
SCSI on the Mac II was theoretically twice as fast as on the SE, potentially matching the speed of USB 1.1 devices, although benchmarks only show it as about 20% faster than the SE in hard drive tests. As with the SE, the Mac II really benefits from a newer hard drive – almost anything built since 1989 can take better advantage of the Mac II’s SCSI bus.
The Mac II and SE Today
These aren’t terribly practical computers today. An SE with System 6 can make a nice word processor or email machine, but avoid TrueType fonts or ATM (Adobe Type Manager), which will slow any 8 MHz Mac to a crawl (that’s being generous). With an ethernet card, it can exist comfortably on a computer network.
Although the SE can run System 7, unless you avoid font rendering (TrueType and ATM) or drop in an accelerator, you generally won’t be happy with its performance. You’ll also need at least 2 MB of RAM to run System 7. If your SE hasn’t already been upgraded to that point, you’re better off sticking with System 6.0.x.
There are even more reasons to avoid the Mac II. The difficulty in obtaining SIMMs larger than 1 MB and the 32-bit “dirty” ROMs severely limit its potential. Worse yet, its PRAM batteries are soldered to the motherboard; when they go, you’ll have to figure out how to replace them without ruining your vintage Mac.
Still, these two Macs helped change the Mac’s direction from being a closed box information appliance into the far more expandable Macs we have known since 1987.
Picking up a Mac II or SE can be a great bit of nostalgia for those of us who first discovered Macs in the late 1980s. They can be a great low-cost introduction to computing for kids. The can be a great reminder of how simple things used to be. And they can be a nice antidote to the overly stylized world of Mac OS X.
March 2, 1987 was the day Macs stopped being considered cute little toy-like computers and became more respectable production machines.
Keywords: #macii #macse #macintoshii #macintoshse
Short link: http://goo.gl/TE5BNB