' Herb's Mac Memory

Mac memory

Most recent revision of this page date Apr 2 2022. This Web page has Memory for PowerMacs and other Apple Mac computers and some cards and accessories. Prices and models change often so monitor these pages! For the other Apple Macintosh parts, systems, printer and other items we sell, check our Mac computer page.

Please consult documentation for your Mac before buying memory. I have a brief document on Macs and memory you may want to look at. Check my Mac Web pointers page for links to Apple's tech docs also - particularly ones on memory. Go to Apple's tech specifications page to access a list of older Apple systems. Also check Apple's archives before 1997 via this link. The search page has a checkbox "archive: include content created prior to 1997" which you MUST check off. As of 2004, relevant Apple documents are:
Power Macintosh: Using FPM, EDO, SDRAM, and SGRAM
Power Macintosh: Memory Configurations
A site search may find specific references on using memory such as 64MB 72-pin SIMMS which are unusual. If you want to know how to read the funny numbers on the DRAM chips themselves (to determine capacity, FPM or EDO, etc) check this document or find similar documents on the Web.

To order, please follow this link for ordering information, terms and conditions, and info about orders outside the USA.

eMac, iMac, G4, memory

I cannot come up with a straightforward, simple explanation of memory requirements for iMacs or eMacs or G4's. Therefore it is up to you the customer to determine what memory you want for your Mac. No returns on memory purchases. For these older Macs, memory is generally too cheap to fuss with or ship back and forth. We MAY be able to test memory on selected Macs, at our discretion. (We've already tested memory on an Apple computer before stocking it.)

Many memory selling Web sites offer recommendations and testing tools. Apple offers some technical guidance on their Web site. The OS9 "System Profiler" report includes a speed description of RAM in iMacs and later systems. Again, KNOW WHAT YOU WANT TO BUY, please do not ask me, I am in a "conflict of interest" to advise you and good advice is not easy.

PC100/66 CL3 or 322 SDRAM, -10 chips: see "grey" PowerMac G3 memory below. Not for Macs above 350MHz.

PC100 CL2 SDRAM, -7 or -75 type chips:
64MB $7, 128MB $12, 256MB $15, 512MB $35 - OUT of 256MB and 512MB as of jan 2008, ask

PC133-labled SDRAM:
128MB $15, 256MB $25, 512MB $55 - limited supplies, ask.

"grey" PowerMac G3 "SDRAM Memory

The PowerMac G3 desktop or minitower, platinum (grey) model uses 3.3V PC-100 SDRAM, 168-pin, 100MHz or -10 speed, 64 bit wide, unbuffered. Faster RAM will also work. The various G3 motherboard revisions can all use 32M, 64M, 128M; revision 3 can use 256Mb SDRAM. Physical space may limit the height of SDRAMs you can use. my PowerMac page for info about the G3 grey/platinum models and their revisions.

PC 66/100 SDRAM for B&W G3's at or below 333MHz: 128MB $8 256MB $12, 512MB ???

PowerMac DIMM Memory

Almost all the PowerMacs, except the very oldest PowerMacs and the later G3's, use 168-pin 5V DIMM DRAM memory. For your Mac, please check your technical specifications or the reference Web links at the top of this page to be sure. We sell PowerMacs on our Powermac Web page.

168-pin 5V (FPM) DIMM DRAM for the 7200, 7300, 7500, 7600, 8500, etc.:
8MB $5, 16MB $9, 32MB $19, 64MB OUT

168-pin 5V EDO DIMM DRAM for the 5400, 5500, 6400, 6500:
(will also work in 7300, 7500, 7600, etc. but NOT in 7200 or 4400 systems)
8MB $5, 16MB $8, 32MB $15, 64MB OUT

Some older PowerMacs use 72-pin SIMM memory; for instance the 6100, 7100, 8100. Check our prices below in our SIMM section.

SIMM Memory

Macs which use SIMM memory are the earliest, pre-PowerMac systems such as the SE, II series, and others which use the 68000 or 68030 or 68040 processor. Some Macs with PowerMac processors also use SIMMS, so for your Mac check your tech specs or the references at the head of this page to be sure. Go to our Mac home page for specific Mac systems we sell.

I also sell these SIMMS to other customers, like PC-compatible customers, or SGI Silicon Graphics customers. Those systems require "parity", a 9th bit. Most Macs don't care if there's a parity bit in installed memory.

30-pin SIMM RAM memory is suitable for Mac Plus, SE, SE/30, Mac II, IIci, IIsi, IIcx, other systems. Please confirm these will be compatible with your system before you order. For instance, Mac II's don't use standard 4MB or 16MB SIMMs; Mac Plus and SE can't use ANY 4MB SIMMS, etc. We sell either 8-chip or 9-chip (parity) SIMMS. Macs ignore parity, old IBM PC's and other systems may require it. We have a few 2-chip and 3-chip SIMMS but many Mac owners don't want these, let me know if you do.

256 Kb 30 pin SIMMS: 8 or 9-chip, 100ns or 120ns. Ask if available, prices depend on details.
1 Meg (1Mb) 30 pin SIMMs, 8-chip or 9-chip. 100ns ask if available. 80ns: 4 for $25. 70ns 4/$29, 60ns 4/$32. Miniumum order of four.
4 Meg (4Mb) 30-pin SIMMs: 8-chip or 9-chip 80ns: $?? each. 70ns $??, 60ns $??
16 Meg (16Mb) 30-pin SIMMs: very limited supply, ask about price and availability
Some SIMMS available with bronze or gold contacts at extra cost, instead of tin, ask.

Memory upgrade modules for the Mac Classic. Apple RAM board with 1 meg on-board, sockets for two 1MB SIMMS. Increases your Classic to 4MB when populated. Ask if available.

64-pin SIMM memory was used on The Mac IIx, Mac IIfx, and Laserwriter IIntx; my supplies are limited but we have them! Also, check my Mac IIfx section .

256K, 1MB or 4MB 64-pin memory SIMMS: ask if available.
note: some slower SIMMS were only for use with the LW IIntx printer controller!.

72 pin SIMM (FPM) RAM memory for some of the 68030 and 68040 series, Quadra, Centris and later Macs including some PowerMacs such as the 6100, 7100, 8100, 5200, 5300. These may or may not have parity, Macs ignore parity. Please confirm these will be compatible with your system. Check Apple's Web site for memory configurations and sizes, look at my list ofApple Web pointers page for specific links. We can test in a few Macs, such as the 6100. One issue with 72-pin SIMMS is whether memory is on BOTH sides or ONE side of the SIMM; some printers and systems treat double sided SIMMS like two seperate SIMMS.

8 meg sold only in quantity, ask. 16 meg $7; 32 meg almost out, ask for price and availability. I might ask more for gold/bronze contacts, many SIMMS have tin (grey). For 64MB SIMMS, see the note below, and ask if I have 64MB RAM available for your particular model of Mac.

Some older 72-pin SIMMS are a little tall. I'll check for physical fit when I can in a particular computer model.

64MB 72-pin SIMMS vary in their construction. Some SIMM models will work with some Macs, some will not work with other Mac models. One issue is physical size. Another issue is "banking", where each 32MB of RAM is addressed in a way that a particular Mac model doesn't support. Apparently it's a result of RAS addressing. This post in macgurus.com appears to explain it in great detail; I do not warrant the explanation. If you want 64MB SIMMS, tell me the model of your Mac and tell me anything else you can. I cannot guarantee your results.

72 pin SIMM EDO RAM memory. Some Macs will run pairs of these faster than FPM memory, but in most systems they will work OK. It's up to you to decide. 16 meg $12; 32 meg $22.

64MB 72 pin FPM SIMMS, no parity. limited number. only warrented and tested for 6100 systems. Check the Web to see if YOUR system can use these. $29 each limited stock.

64MB 72 pin EDO SIMMS no parity, 3.3V 4K refresh? 50ns. Confirm these will work in your computer. $29 each limited stock.

128MB 72 pin EDO SIMMS 16 DRAM chips are 3.3V 16MB X 4 CMOS EDO 4K refresh, no parity. Chips are SEC KM44V16104CS-6 . Worked in a PowerMac 6100/66. Reported to work in a Performa 550 and 575. Not tested in a few years. Ask if still available and price.

VRAM Memory

VRAM and cache are sometimes available, describe your Mac model and ask for prices! Also check for your Mac model on our Web site, we may have VRAM priced with it. Please determine if your Mac model needs specific speeds such as 70ns, 80ns, 100ns; check the Web and Apple's Web site for these specifications for your model.

68-pin VRAM, 256K, example Apple p/n 630-0044, 820-0269; for 7100 video cards, 80ns or 100ns. out, not cheap
68-pin VRAM, 512K, example Apple p/n 820-0625; for 7100 video cards, 80ns or 100ns, OUT, not cheap.
333-1072G, 112-pin Apple 1MB VRAM for PowerMac 7200 7300 7500 7600 8500 8600. $10 each
333-1093G, 112-pin Apple 1MB VRAM (2 chip) for PowerMac 7200 7300 7500 7600 8500 8600. $12 each
3.3V 83 MHz 144-pin SO-DIMM or SGRAM, for G3 motherboards and some G3, G4 video cards. 2MB $15, 4MB $20 each.

Cache Memory

Cache is the memory associated directly with the processor. Use of it speeds up execution of programs. Typically it is added to a ROM or L2 socket. Cache is sometimes available from me, describe your Mac and ask for prices! Also check for your Mac model on our Web site, we may have cache priced with it.

Herb Johnson
New Jersey, USA
here's how to email @ me and order
Copyright © 2022 Herb Johnson