Apple Powermac 7300/166mHz Computer (M3979)

The Apple Power Macintosh 7300/166 (Model Number: M3979), based on the TNT architecture uses the same “Outrigger” case as the Powermac 7600 PowerPC computer, but features an enhanced PowerPC 604e CPU. However, it no longer came with the video in capability the 7600 had, which possibly accounts for the fact that this is the only time that Apple used a lower model number for an upgraded model. Apart from that, the 7300 is more closely related to the 7600 than to the Apple Powermac 7200, with features such as a processor daughtercard and interleaved RAM.  The exterior of the PowerMac 7300 is very similar to the Apple Macintosh IIvi and more recent Macintosh Centris 650. However, internally, they are very different.


The Apple Power Macintosh 7300/166, based on the TNT architecture powermac 7300 motherboardfeatures a 166  MHz PowerPC 604e processor, 32 MB of RAM, and a 2.0 GB hard drive in a well-designed, easy-to-upgrade desktop case.

The 166 mHz 604e processor has a processor bus speed of 41.5mHz and sits on a daughtercard that is mounted to the motherboard.    A set of 8 memory card slots adorn the motherboard, each accepting 168pin 70 ns DRAM DIMMS. It does not require DIMMS to be installed in pairs. Officially, this model supports a maximum of 512 MB of RAM. However, third-parties have discovered that it actually can support 1024 MB (1.0 GB) of RAM with eight 128 MB memory modules.

The Powermac supports 33mHz PCI cards in it’s 3 PCI slots. A seperate Cache module could be added to the motherboard (max 1MB).  Like many of the PowerMac range, a seperate ROM was included on the motherboard, similar to a 72 pin SIMM, it gave the computer it’s personality.

The Powermac 7300 series was released along side the Minitower Powermac 8600 and the Powermac 9600 tower. It replaced both the Power Macintosh 7200 and the Power Macintosh 7600, and was itself discontinued in favor of the Power Macintosh G3 desktop model in November 1997.


This model has two 3.5″ drive bays (one is internal and occupied by a hard drive, and one is external and intended for a Zip 100 drive). By default, the external 3.5″ bay is free. The system also has an external 5.25″ drive bay occupied by the optical drive.


The Powermac range of computers (including the 7300/166) offer a number of ports that have been included on Apple Desktops since their inception.  These include External SCSI (25 pin), AAUI Ethernet, 10 Base-T ethernet, Modem port, Printer port, video out (DB 15), ADB port and sound in and out via 3.5mm jacks.

Video & Graphics:

Adjacent to the processor is a series of 4 VRAM slots, each capable of accepting MB memory sticks.*With the default 2 MB of VRAM, this model supports a single display at 512×384, 640×480, 800×600 or 832×624 at 24-bit, 1024×768 or 1152×870 at 16-bit, and 1280×1024 at 8-bit.

With the maximum 4 MB of VRAM installed, it supports 512×384, 640×480, 800×600, 832×624, 1024×768, or 1152×870 at 24-bit and 1280×1024 at 16-bit.

Introduction Date: February 17, 1997 Discontinued Date: November 10, 1997
Processor Speed: 166 MHz Processor Type: PowerPC 604e
Details: This model has a 32-bit processor and a 64-bit data path.
Processor Upgrade: Daughtercard FPU: Integrated
System Bus Speed: 41.5 MHz Cache Bus Speed: N/A
ROM/Firmware Type: Macintosh ROM ROM/Firmware Size: 4 MB
L1 Cache: 64k L2 Cache: 256k
RAM Type: 168-pin DIMM Min. RAM Speed: 70 ns
Details: Supports eight 70 ns 168-pin DIMMs.
Standard RAM: 16 MB Maximum RAM: 1.0 GB*
Motherboard RAM: None RAM Slots: 8
Video Card: Dedicated* VRAM Type: 1 MB VRAM DIMM*
Details: *By default, this model has 2 MB of VRAM installed as two 1 MB VRAM DIMMs.
Standard VRAM: 2 MB* Maximum VRAM: 4 MB*
Display Support: Single Display* Resolution Support: 832×624*
Standard Hard Drive: 2.0 GB Int. HD Interface: SCSI
Standard Optical: 12X CD-ROM Standard Disk: 1.44 MB (Manual)
Standard Modem: None Standard Ethernet: AAUI, 10Base-T
Expansion Slots: 3 PCI Expansion Bays: 2 3.5″
Case Type: Desktop Form Factor: Power Mac 7500
Apple Order No: M5542J/A* Apple Subfamily: Power Mac 7300
Details: *M5542J/A is the order number for this model in Japan. Order numbers in other countries differed.
Apple Model No: M3979 Gestalt ID: 109
Battery Type: 3.6V Lithium Battery Life: N/A
Original Mac OS: 7.5.5 Supported Mac OS: 7.5.5-9.1
Details: Earlier and later versions of the Macintosh System/Finder and Mac OS are not supported.
Dimensions: 6.15 x 14.4 x 16.9 Avg. Weight: 22.0 lbs (10 kg)