ktrostel@athena.mit.edu (Ian Dowell) (08/02/89)
What is involved in upgrading RAM on a Mac IIcx? Is it really as simple as buying 1M SIMMs (for ~$100?) and dropping them in sockets on the appropriate board? Are there other considerations? (speed? pairing?) Thanks for any help. If I get e-mail I will summarize to the net. Please excuse my ignorace and point me to an appropriate article or reference if possible... Ian Dowell ktrostel@athena.mit.edu
ktrostel@athena.mit.edu (Ian Dowell) (08/08/89)
>What is involved in upgrading RAM on a Mac IIcx? Is it >really as simple as buying 1M SIMMs (for ~$100?) and >dropping them in sockets on the appropriate board? >Are there other considerations? (speed? pairing?) >Thanks for any help. If I get e-mail I will summarize >to the net. Thanks for all the responses! The memory that you install needs to be at least 120ns (speed) and the SIMMs must be installed in sets of 4, meaning that you have to invest at least $400. Let me know if you have any other questions. -Michael -- Michael Niehaus UUCP: <backbones>!{iuvax,pur-ee}!bsu-cs!mithomas Apple Student Rep ARPA: mithomas@bsu-cs.bsu.edu Ball State University AppleLink: ST0374 (from UUCP: st0374@applelink.apple.com ) you MUST be very careful of two things. #1 STATIC ELECTRICITY Even if you cant feel the spark, it WILL destroy the SIMM and possibly the motherboard! This is no joke. Use a wrist strap grounded to the power supply case or keep touching the case every few seconds. You must have the unit plugged in BUT NOT turned on to have it connected to ground. #2 The SIMM sockets are fragile. It takes a little skill to remove the old 256K SIMMS to insert the 1MB SIMMS. Technology Works supplies a good instruction manual with their SIMMS. They ship Federal Express and I had my SIMMS 17 hours after I ordered them! I LIKE THIS COMPANY! They also have a lifetime warranty on the SIMMS. A tip: Always insert SIMMS on an angle, then raise to perpendicular to snap into place. NEVER insert straight down. It will bend the socket connectors. Use an angle of about 45 degrees. If you hear a strange four note tune when you start up your Mac IIcx after the SIMM instalation, it means that the SIMMS are not quite in properly. This happened to me, and I removed them, and reinserted them to get it to work properly. HEED the warning about waiting 5 minutes after turning off the Mac before doing anything inside the box! This is to allow the power supply to drain to a low (safe to the chips) level, not for your safety. Technology Works: (800) 622-2210 Hard Drives International: (800) 234-DISK --keith It's as simple as buying the proper number of 1MB SIMMs and dropping them in the sockets. The MacII* machines require that each set of 4 SIMMs be the same size. So, you can have 1, 2, 4, 5, or 8 Mbytes using various combinations of 1MB and 256K SIMMs. So, you could buy a single SIMM, but it wouldn't do you much good. I believe that the IIcx will take any size SIMMs, but low profile SIMMs hold their value better, since SE owners can use them. Also, I think the IIcx will take 100 and 120ns SIMMs, but you may want to go with 80ns SIMMs if you may upgrade to a faster system later. After you have the memory, it's easy if you're careful. You have to put the bigger SIMMs (in the 1, 4, or 5 MB cases) in the "left" (from the front) sockets. Also, SIMMs go in at an angle (the top is more to the left). You slide the SIMM down into the socket and then rotate it to the right to click into the holder. -- David Elliott dce@Solbourne.COM ...!{boulder,nbires,sun}!stan!dce Back issues of Macworld and MacUSer have instructions as well as a Tech Note (somewhere around 150). For a MacIIcx, I'll assume they are the same as the II. Your SIMMS have to be at least 120ns (no worry since most people offer that and usually down to 80ns if you want to pay for it - the lower speed won't help your system, at least for now it won't). The Mac II series needs SIMMS in banks of four and they all have to be the same speed from what I understand. If you only have 256K SIMMS(i.e. 1 MB of memory) in right now, you'll have to move those to the other bank when installing 1MB SIMMS (can't remember why, but it's the rule). If you have 4MB of memory (4x1MB SIMMMS) just pplace your SIMMS in the other bank. A bank refers to the set of four mini-card connectors on the motherboard (open up you IIcx and take a look). Johnny Lee jlee4@orchid.waterloo.edu !watmath!orchid!jlee4 Yup... it's that easy. There are no resisters to cut, jumpers to jump, or switches to switch. Just drop in the new RAM and the machine automatically recognizes it. All the SIMMs must have an access time of 120nS or faster, and the SIMMs in one row must have the same speed rating (the SIMM slots in the Mac II, IIx, IIcx, and SE30 are divided into two rows... each row comprising 4 SIMM slots). Incidently, you aren't limited to 1MB SIMMs; You can also use 4MB or 16MB SIMMs in a row. (Of course, 4MB SIMMs are still very expensive, and you can't get 16MB SIMMs yet... but when you can you'll be able to have 128MB on you mac's motherboard :-) Also, the rumers that I hear say that the new Mac IIci will use 100nS or faster SIMMs. I bought 80nS SIMMs myself; They should be fast enough for the next couple of years. :-) Cheers, Norm For details on memory configs, check out tech note 176 from Apple. It is available for anonymous ftp from sumex-aim.stanford.edu. If you have the disk space you can get the hypercard technote stack which has all of the notes and figures, and an index. For an SE/30, II, IIx, or IIcx there are 8 memory slots. Each group of 4 must be populated fully or not at all. If a group (or Bank) is populated, it must contain 4 of the same size and speed of SIMM. 120ns or faster (most places are selling 80 or 100ns these days, it seems) SIMMs are needed. Lastly, Bank A must always be populated, AND contain the LARGEST capacity SIMMs. So, you can get SIZE Bank A contents Bank B contents 1MB 4x256K empty 2MB 4x256K 4x256K 4MB 4x1MB empty 5MB 4x1MB 4x256K 8MB 4x1MB 4x1MB Hope this helps, Ric Ric Anderson Bitnet: Ric@Arizrvax Member of the Technical Staff Internet: ric@cs.arizona.edu University of Arizona UUCP: {cmcl2,noao,uunet}!arizona!ric Department of Computer Science AT&T: (602) 621-4048 Gould-Simpson Room 721 Tucson, Arizona 85721