Macintosh LC III

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MacLCIII.jpg
Macintosh LC III
Performa 450
CPU: 25 MHz Motorola MC68030
RAM Type:72-pin SIMM
Maximum RAM: 36 MiB
Expansion slots: Enhanced LC-PDS
Supported OS: System 7.1 - Mac OS 7.6.1
Introduced:February 10 1993
Discontinued:February 14 1994
MSRP:$1350 (US)
Full Specifications


Third in the series of LC Machines, the LC III was far more than just a name change and a speed bump; it actually addressed many of the underlying issues in the entire LC line.

History

The LC and LC II had both been brave attempts to create low cost Macintoshes that were within the reach of everybody. From a cost perspective they were great. From a technical perspective they definitely weren't. Both machines had used 32-bit processors — the 68020 in the case of the LC; the 68030 in the LC II — but had run them on 16-bit data buses, effectively crippling them before either ever left the drawing board. There were also problems with memory, as both machines used the older 30 pin SIMMs and had a memory ceiling of just 10 MiB. If the new LC III was going to be given a warm welcome, it was going to have to address a lot of issues.

Amongst these was the small matter of the crippled data bus/CPU that had been at the heart of the LC's performance issues — both machines did run awfully — with Apple actually making the effort to solve the problem, this time around. Not only would the LC III run the venerable Motorola 68030 at a speedy 25 MHz, it would also couple it with a proper 32-bit data bus — at last the CPU could show what it was capable of. This already was a massive bonus for buyers, but Apple didn't stop there, and looked into resolving the issue of RAM: the twin 30-pin SIMM slots gave way to a single 72-pin slot. It might have been one slot less, but users could now expand their machines up to a far healthier 36 MiB (the machine still came with 4 MiB of on board RAM).

Apple had also finally got the message and looked into improving the on board video. The LC and LC II had both been limited to 512 KiB of VRAM (allowing, at best, 640×480 in 256 colours), but the LC III came with 512 KiB VRAM pre-installed and the option to upgrade to 768 KiB — allowing for a resolution of up to 832×624 in 65,536 (16-bit) colours. The same went for the expansion slot, with the original LC PDS slot being replaced by a new, 'enhanced' (LC III) PDS slot.

Given all of this, Apple could have been forgiven for increasing the list price of the new machine but, even here, they put customers first with the LC III being cheaper than both of its predecessors, weighing in at a bargain $1350 — just over half the cost of the original LC.

Full Specifications

  • General
    • CPU: 25 MHz Motorola MC68030
    • ROM: 512 KiB
    • Bus Speed: 25 MHz
    • Data Path: 32-bit
    • RAM Type: 72-pin SIMM (100 ns)
    • Standard RAM: 4 MiB
    • RAM Onboard: 4 MiB
    • RAM Slots: 1
    • Maximum RAM: 36 MiB
    • Cache: ½ KiB (L1)
  • I/O & Expansion
    • ADB: 1
    • Serial: 2
    • SCSI: 1 (DB-25)
    • Floppy Connector: 1
    • Audio In: Mini-jack
    • Audio Out: 8-bit 22 KHz mono (mini-jack)
    • Built-in Speaker: Mono
    • PDS Slot Type: Enhanced LC
  • Storage
    • Hard Drive: 40 MiB - 160 MiB
    • Hard Drive Type: SCSI
    • Floppy Drive: One 1.44 MiB SuperDrive
  • Video
    • Max Resolution: 512×384, 640×400 (16-bit), 640×480, 832×624 (8-bit), 640×480, 832×624 (16-bit — 768 KiB VRAM), 640×870 (4-bit), 640×870 (8-bit — 768 KiB VRAM)
    • Standard VRAM: 512 KiB
    • VRAM Onboard: 0 KiB
    • VRAM Slots: 1
    • Maximum VRAM: 768 KiB
    • Video Out: DB-15
  • Miscellaneous
    • Apple Model Number: M1254
    • Codename: Elsie III, Vail
    • Gestalt ID: 27
    • Power: 50W
    • PRAM Battery: 3.6V Half-AA
    • Case Style: LC
    • Dimensions: 12.2" x 15.3" x 2.9" (W x D x H)
    • Weight: 8.8 lbs.
    • Mac OS Support: System 7.1 - Mac OS 7.6.1 (with help of the software "Reborn" up to Mac OS 8.1)
    • System Enabler: 003
    • Introduced: February 10 1993
    • Introduced: February 14 1994
    • MSRP: $1350 (US)

Upgrade options and modifications

Usual hardware upgrades for the LCIII include a RAM upgrade to 36 MiB or even up to 132 MiB, VRAM Upgrade to 768 KiB, a math coprocessor (FPU) and a PDS expansion card, like an ethernet network adapter or an additional graphics output card. With a small modifiction to the mainboard it is possible to set the bus clock frequency from 25 MHz to 33 Mhz, combined with application of passive heatsinks to cpu and fpu. To bring the system to maximum performance an accelerator card with 68040 CPU could be installed (several cards were available, like Daystar Turbo 040).

Mainboards of the LC series with the pizzabox shaped case share the same mainboard form factor. The most effective upgrade path will be a mainboard swap with a LC/Performa 475 or a Quadra 605. Do not rip apart good working machines, please. Note: the Apple Portrait monitor resolution is not supported by the the LC 475 onboard video.

More Information