The Quadra 840av has no system memory on its motherboard and has four 72-pin SIMM sockets for memory expansion to 128 MB.
The Centris 660av and Quadra 660av are identical except for the name plate. They have 4 MB of RAM soldered to the motherboard and two 72-pin SIMM sockets for memory expansion.
Whether marked Quadra 630 DOS Compatible, LC 630 DOS Compatible, or Performa 631 or 640, these models have 4 MB of RAM soldered to the motherboard, two 72-pin SIMM sockets for memory expansion up to 52 MB, and usually a DOS Compatibility card as well.
This page provides information about modifying the motherboard in your Quadra, Performa, or LC 630 series computer. Such modifications are not authorized by Apple. Any modifications you perform on your Mac may damage it. Modifications are done at your own risk.
Whether marked Quadra 630, LC 630, or Performa 63x, this model has 4 MB of RAM soldered to the motherboard and a single 72-pin SIMM socket for memory expansion up to 36 MB. (The DOS Compatible version and some 630s have a different motherboard with two SIMM slots and are covered on a separate page.)
The Mac LC/Performa 580 shipped with 4 MB soldered on the motherboard and two 72-pin SIMM sockets for memory expansion – twice as many as the LC 550 and 575 – for up to 52 MB total system memory, the most possible in any 500-series Mac. Like other 500-series Macs, it has a slide-out motherboard.
The Quadra 605 (and its twins, the LC 475 and Performa 475/476) has 4 MB of RAM soldered to the motherboard and a single 72-pin SIMM socket for memory expansion. It supports up to 36 MB of system memory.
The LC 520 and Performa 520 are twins, larger versions of the all-in-one Macs of the past. They have 4 MB soldered on the motherboard and a single SIMM socket for memory expansion. Like other 500-series Macs, the 520 has a slide-out motherboard.
The Mac TV is pretty much a black LC 550 with a built-in TV tuner and a remote control for the TV portion of the computer. It has 4 MB soldered on the motherboard and comes from the factory with a 1 MB 72-pin SIMM in its only memory socket. Mac TV only had one […]
The Mac LC III and its 33 MHz siblings – the LC III+, LC 460, and Performa 460 – have 4 MB of RAM soldered to the motherboard and a single 72-pin SIMM socket for memory expansion.
The Mac IIvx, Mac IIvi, and Performa 600 were odd ducks, running a 16 MHz motherboard when most of Apple’s other machines were already faster than that. Since the IIvi had a 16 MHz 68030 CPU, that wasn’t a bottleneck, but the IIvx and Performa 600 had 32 MHz CPU, which were hobbled by the […]
The Color Classic has 4 MB of system memory soldered to its motherboard. There are two SIMM sockets that can be used to expand it to 6 MB, 8 MB, or 10 MB.
The Mac LC 550 and 575, also sold as the Performa 550 and 575 to the home market, have 4 MB of RAM soldered to the motherboard and a single 72-pin SIMM socket for memory expansion. They can handle up to 36 MB of memory.
The Centris 610, Quadra 610, and Apple Workgroup Server 60 have 4 MB of RAM soldered to the motherboard and two 72-pin SIMM sockets for memory expansion as far as 72 MB.
The Centris 650 has 4 MB or 8 MB soldered to the motherboard; the Quadra 650 has 8 MB on the motherboard. Each has four 72-pin SIMM sockets for memory expansion.
The Quadra 800 and Apple Workgroup Server 80 have 8 MB of memory on the motherboard and a single bank of four SIMM sockets for memory expansion as far as 136 MB. This was one of the first generation of Macs to use 72-pin SIMMs.
The Mac LC II (a.k.a. Performa 400, 405, 410, and 430) has 4 MB of RAM soldered to the motherboard and room for two additional SIMMs. (Apple says that some LC IIs have 2 MB of onboard RAM, but I have never run into one.)
The Mac Classic II (a.k.a. Performa 200) has 2 MB soldered to the motherboard. There are two SIMM sockets, which can be used to expand this Mac to a total of 4 MB, 6 MB, or 10 MB.
The Quadra 900 and 950 have no RAM on the motherboard and 16 sockets for four banks of memory expansion. They shipped with 8 MB and can support up to 256 MB of system memory – twice as much as any previous Mac.
The Quadra 700 has 4 MB soldered to the motherboard and one bank of 30-pin SIMMs for memory expansion, allowing up to 68 MB of system memory.
The Mac Classic has 1 MB of memory soldered to the motherboard. A second megabyte is added with a memory expansion board, which also has two SIMM sockets. Using these sockets, RAM can be expanded from 2 MB to 2.5 MB or 4 MB.
The Mac LC has 2 MB of RAM soldered to the motherboard and two SIMM sockets for upgrading memory to as much as 10 MB.
The Mac IIsi is essentially a more compact version of the Mac IIci with no NuBus expansion slots and operating at a reduced CPU speed. It uses the same architecture, sharing the first 1 MB of RAM for video and computing.
Apple broke the speed envelope with the Mac IIfx – the 40 MHz 68030 CPU on a 40 MHz data bus left everything else in the dust. Because it needed faster memory than any previous Mac, it used a special 64-pin dual-ported SIMM. It was the first Mac to ship with 4 MB of RAM.
The Mac IIci took the popular Mac IIcx design and replaced its 16 MHz logic board with a 25 MHz 68030-based design. New features included built-in video and a Level 2 (L2) cache socket. The IIci was the first Mac with “32-bit clean” ROMs.
The Mac SE/30 shipped from the factory with 1 MB installed. It can be upgraded to 2, 4, 5, 8, 16, 17, 20, and 32 MB* configurations using 120ns or faster 1 MB or 4 MB 30-pin SIMMs – and as high as 128 MB using 16 MB SIMMs.
The Mac IIcx was Apple’s first compact model in the Mac II series, essentially a Mac IIx with three NuBus expansion slots instead of six and a smaller power supply. Like the Mac II and IIx, it can only access 8 MB of memory under System 6 and earlier. You need to run some version […]
The Mac IIx was Apple’s first 68030-based computer. You need to run some version of System 7 to have access to the 32-bit option and use the free Mode32 utility to let the IIx run in 32-bit mode. This allows users to use more than 8 MB in the IIx.
The Mac II was Apple’s first modular Macintosh. Using a 68020 CPU instead of the older 68000, it can address far more memory by using 32-bit addressing. Although it took System 7 to provide the 32-bit option and Mode32 to let the Mac II operate in 32-bit mode, this allowed users to use more than […]
The Mac SE shipped from the factory with 1 MB installed in the form of four 256 KB SIMMs. It can be upgraded to 2 MB, 2.5 MB, and 4 MB configurations using 150ns or faster 1 MB 30-pin SIMMs.