michali@savax.UUCP (Paul C. Michali) (12/09/88)
Someone had mentioned that memory on the PLUS and SE had to be done in pairs. Is this true for the Mac II? Can one have 3MB ( four 256K and two 1M SIMMS)? We are looking to buy a Mac and can get a 2M SIMM package from National Semi for a good price, but I am concerned abouth whether I must trash two of the 256K SIMMS to end up with 2.5MB or just insert two 1M SIMMS to get 3MB. HELP!!! We ahve to make a decision soon (company purchase). Thanks in advance, PCM
earleh@eleazar.dartmouth.edu (Earle R. Horton) (12/10/88)
In article <825@savax.UUCP> michali@savax.UUCP (Paul C. Michali) writes: >Someone had mentioned that memory on the PLUS and SE had to be done in pairs. > >Is this true for the Mac II? Can one have 3MB ( four 256K and two 1M SIMMS)? > Page 207 of Macintosh II manual: "Your computer comes with 1 megabyte (1 MB) of memory on the main logic board. You can upgrade your system to 2, 4, 5, or 8 megabytes of memory." ^ ^ ^ ^ You can buy four 256k SIMMs, or you can buy four 1 M SIMMs. If you have a Macintosh II, you must buy four SIMMs of the same type at a time. SE and Mac Plus: 512k, 1, 2, 2.5 or 4 M. SIMMs are purchased in pairs. Earle R. Horton. 23 Fletcher Circle, Hanover, NH 03755 (603) 643-4109 Graduate student.
kehr@felix.UUCP (Shirley Kehr) (12/11/88)
In article <825@savax.UUCP> michali@savax.UUCP (Paul C. Michali) writes:
<Someone had mentioned that memory on the PLUS and SE had to be done in pairs.
<Is this true for the Mac II? Can one have 3MB ( four 256K and two 1M SIMMS)?
<We are looking to buy a Mac and can get a 2M SIMM package from National Semi
<for a good price, but I am concerned abouth whether I must trash two of the
<256K SIMMS to end up with 2.5MB or just insert two 1M SIMMS to get 3MB.
<PCM
With a Mac II you have the option of buying it with 1Mbyte and adding 4
256K chips to bring the total to 2 Mbytes. Or you can buy 4 1Mbyte SIMMs
and bring the total to 5 Mbytes. Beyond that you throw away the original
1 Mbyte and put in 4 more 1 Mbyte SIMMs for a total of 8 Mbytes.
Most people I've talked to won't sell Mac II SIMMs (1Meg) two at a time
because you have to do 4 at a time. Be
sure the 2Mbyte SIMM package is really for a Mac II, and get two of them.
You can also buy a Mac II with 4 Mbytes (and a 40 Meg disk). I recently
asked for a quote, and because I already had the hard drive, I just wanted
a 4 or 5 meg Mac II - period. It was more expensive to buy the 1 meg version
and add memory than to buy the 4 meg version with the hard disk.
Shirley Kehrjeff@drexel.UUCP (Jeff White) (12/12/88)
In article <825@savax.UUCP>, michali@savax.UUCP (Paul C. Michali) writes: > Someone had mentioned that memory on the PLUS and SE had to be done in pairs. > > Is this true for the Mac II? Can one have 3MB ( four 256K and two 1M SIMMS)? No. SIMMs are installed in pairs in SE's and Plus's because the data bus in those machines is only 16 bits wide (each SIMM accounts for 8 bits). The Mac II, on the other hand, has a 32 bit bus, and thus memory has to be installed 4 SIMM's at a time. Jeff White Drexel University - ECE Dept. rutgers!bpa!drexel!jeff
stuartb@microsoft.UUCP (Stuart Burden) (12/12/88)
In Article <825@savax.UUCP> michali@savax.UUCP (Paul C. Michali) writes: | Someone had mentioned that memory on the PLUS and SE had | to be done in pairs. On the Plus and SE, there are two banks of two SIMM slots. Each bank must be fully populated for the memory in either bank to be recognised. | Is this true for the Mac II? Can one have 3MB ( four 256K | and two 1M SIMMS)? The Mac ][ has 2 banks of four SIMM's. Again, each bank must be fully populated for the memory in either bank to be used by the Mac. Therefore it is not possible to use just one 1meg SIMM to upgrade the second bank on the Mac ][ to 2megs (or three). Upgrade configurations from 1 meg are: 2 meg (second bank populated with 256K SIMM's) 5 meg (second bank populated with 1 meg SIMM's) 8 meg (remove 1st bank of 256K SIMM's and fully populate both banks with 1 meg SIMM's) | We are looking to buy a Mac and can get a 2M SIMM package | from National Semi for a good price, but I am concerned | abouth whether I must trash two of the 256K SIMMS to end | up with 2.5MB or just insert two 1M SIMMS to get 3MB. Again, you will have to install 4 SIMM's, or the Mac will not recognise the memory in that particular bank (the 2.5 meg configuration is possible on the Plus and the SE, where one bank would still have two 256K SIMM's, and the other bank will have two 1 meg SIMM's). | Thanks in advance, PCM Stu. __Paths to my door:_______________________ microsoft!stuartb@beaver.cs.washington.edu - Usual disclaimer, that all microsoft!stuartb@uw-beaver.arpa - the above is pure fantasy microsoft!stuartb@uunet.UU.NET - and Microsoft only [DE01HB]stuartb@DASNET# {from AppleLink} - gave me the Mountain Dew stuartb@microsoft.uucp {well connected} - to dream it all in a D2012 {AppleLink - shared account} - caffeine haze :-) __________________________________________________________________________
wards@pc.ecn.purdue.edu (Sherman Ward) (12/14/88)
In article <74566@felix.UUCP> kehr@felix.UUCP (Shirley Kehr) writes: >In article <825@savax.UUCP> michali@savax.UUCP (Paul C. Michali) writes: ><Someone had mentioned that memory on the PLUS and SE had to be done in pairs. ><Is this true for the Mac II? Can one have 3MB ( four 256K and two 1M SIMMS)? ><PCM > >With a Mac II you have the option of buying it with 1Mbyte and adding 4 >256K chips to bring the total to 2 Mbytes. Or you can buy 4 1Mbyte SIMMs >and bring the total to 5 Mbytes. Beyond that you throw away the original >1 Mbyte and put in 4 more 1 Mbyte SIMMs for a total of 8 Mbytes. >Most people I've talked to won't sell Mac II SIMMs (1Meg) two at a time >because you have to do 4 at a time. Be sure the 2Mbyte SIMM package >is really for a Mac II, and get two of them. You can also buy a >Mac II with 4 Mbytes (and a 40 Meg disk). . . . . >Shirley Kehr Am I understanding correctly that MacII (1Meg) SIMMs are different than MacSE SIMMs (1Meg)?? (Speed differences only?? 150NS vs <150NS???) I have been checking into what I can do with my 6 extra 256K (150 NS) SIMMs that I pulled from Mac SEs. To MY UNDERSTANDING (please correct me and I'm certain somebody knows more than I do :-) the MacSE is designed for use with 150NS (or faster) SIMMs, whereas the MacII is designed for use (and shipped) with 120NS SIMMs. Now, the MacSE has 4 SIMM slots. Shipped with 4 256K (150NS) SIMMs (1Meg). To go to a 2Meg or 2.5Meg you pull 2 of the 256's and replace with 1Meg SIMMs. In order for the SE to understand the change in memory you (read "Authorized repair Persons" :-) need to clip off a resistor. For a 4Meg upgrade, you jerk all 4 of the 256's and replace with 1Meg SIMMs. And now you have 2 or 4 (150NS) 256K SIMMs which do not have a home :-( The MacII has 8 SIMM slots. The MacII (1Meg) has 4 slots filled with 256K SIMMs (120NS). Leaving 4 open slots. I don't know the complete details of installation, but I ASSUME (I know, A** out of U & ME) to go to 2Meg just add 4 256K SIMMs (120NS), 5Meg add 4 1Meg (120NS or faster???) SIMMs (clip a resistor????), 8Meg pull the 4 256's and replace with 1Meg SIMMs. Questions: 1) Is there a good (and easy) home for 256K (150NS) SIMMs?? (In a Laserwriter+, LaserwriterNT, or an IBM AT class machine?) (I would hate to trash them). 2) Can I replace ALL 120NS SIMMs in a MacII and put in 150NS SIMMs in as replacements?? Any mechanical/technical problems using 150NS chips in a machine designed for 120NS Chips?? (I realize thru-put would suffer but at least I could use my 150NS 256's :-) 3) Does a MacII puke with different speed 256's inside? 4) What is the slowest speed SIMM a MacSE or MacII will accept without technical difficulties?? I know that slower chips cost less $$$. Later, Sherman +-------------------------------------------------------------------+ -- +SNAIL: Sherman Ward / Freshman Engineering / Purdue University / + + Rm 221 Engineering Admin. Bldg. / West Lafayette, IN 47907 + +-------------------------+----------------+------------------------+ + wards@pc.ecn.purdue.edu + (317) 494-3976 + I believe in Murphy! +