cmkuo@cs.utexas.edu (Chin-Ming Kuo) (02/14/89)
I am seriously considering a SE/30, and have the following questions for you Mac gurus. 1. Since there's a little chance I can get enough money for all 4 1M SIMMs, I am planning to use the 256K SIMMS to bring the SE to 2M total. There's a chance I might get a hold of some 256Kx1 chips and some 256Kx4 SIMMs ( what is this!), all are 120ns. can I make something useful out of these? Or a simple question, what exactly is the configuration of the 256K SIMM used in the SE30/ II? Are there 8 256Kx1 on a module and I need 4 of the modules to make 1M? 2. Why AUX requires a min. 80M hard drive? Is it simply the requirement of size, or the system drive must be at least 80M? Eventually I will get AUX, so can I get a 40M hd for now and get a second 40M hd later when I really need to run AUX? Thanks, -- Chin-Ming Kuo cmkuo@cs.utexas.edu cs.utexas.edu!cmkuo -- Chin-Ming Kuo cmkuo@cs.utexas.edu cs.utexas.edu!cmkuo
mithomas@bsu-cs.UUCP (Michael Thomas Niehaus) (02/15/89)
In article <4776@cs.utexas.edu>, cmkuo@cs.utexas.edu (Chin-Ming Kuo) writes: > 1. Since there's a little chance I can get enough money for all 4 1M > SIMMs, I am planning to use the 256K SIMMS to bring the SE to 2M > total. There's a chance I might get a hold of some 256Kx1 chips and > some 256Kx4 SIMMs ( what is this!), all are 120ns. can I make > something useful out of these? Or a simple question, what exactly is > the configuration of the 256K SIMM used in the SE30/ II? Are there 8 > 256Kx1 on a module and I need 4 of the modules to make 1M? I don't understand. I think that you may have been confused by previous postings. There are currently two types of SIMMs that are usable in the Mac: 256K SIMMs and 1MB SIMMs. The '256Kx4' means that you are using four of the 256K chips. With the SE/30, you must put the SIMMs into the machine in sets of four. That means if you buy a 1MB SE/30, you can install four of the 256k SIMMs (256kx4) to bring your machine to two meg. But to go any farther than that, you will have to remove some (4) of those and install some (4) 1MB chips to bring your system to 5MB. > 2. Why AUX requires a min. 80M hard drive? Is it simply the > requirement of size, or the system drive must be at least 80M? > Eventually I will get AUX, so can I get a 40M hd for now and get a > second 40M hd later when I really need to run AUX? A/UX is like any UNIX system: it needs lots of disk space for utilities. I suppose you could get by with running A/UX on a system with a 40MB hard drive, but you would probably have to strip it down (maybe get rid of manual pages, utilities that are not used, etc.). But one question: if you are considering a SE/30, are you sure that you are wanting to consider A/UX? You do know that A/UX on an SE/30 is not supported by Apple (maybe in the future, but not now), don't you? > Chin-Ming Kuo > cmkuo@cs.utexas.edu > cs.utexas.edu!cmkuo Maybe I made a mistake in my previous postings in referring to memory using the '256Kx4' notation. Maybe it should have been '4x256K'? I don't know... I know the Macintosh creates some confusing situations, especially with memory upgrades, so I completely understand why some people are concerned with what they can and can't do. I hope with the help of the people on the net, we can prevent problems like those that occurred here at Ball State last year: 2MB memory expansion kits were purchased, one for every Mac II that was purchased earlier. No one knew that you need 4M to upgrade, so it ended up that every other person received their upgrade... Case learned: if you are not absolutely sure, make sure you ask someone. Michael Niehaus Apple Student Rep Ball State University UUCP: ..!{pur-ee,iuvax}!bsu-cs!mithomas AppleLink: ST0374
sklein@cdp.UUCP (02/22/89)
256Kx1 chips are used in Macs. 256Kx4 chips are four bit wide, so you only need two of these chips to get 256K bytes. Chips are rated in K (thousand) BITS, while actual RAM is measured in KBYTES, where 8 bits = 1 byte. So, for a SIMM to have 256K bytes, it must have eight 256Kbit chips on it. Make sense?