johnston@minnie.me.udel.edu (06/05/91)
Will the SE/30 or IIcx recognize 2 MB SIMMs? From 5 meg, it seems that one has the option of going to 20 with 4 x 4 MB, or 8 with 4 x 1 MB. Too much, or not enough! Twelve seems about right; 32-bit brouhaha notwithstanding, it seems a reasonable amount for a 16 MHz '030. Is this possible? -- Bill (johnston@minnie.me.udel.edu)
afry@uhura.cc.rochester.edu (Alan R. Fry) (06/05/91)
In article <55485@nigel.ee.udel.edu:> johnston@minnie.me.udel.edu writes:
:>Will the SE/30 or IIcx recognize 2 MB SIMMs? From 5 meg, it seems
:>that one has the option of going to 20 with 4 x 4 MB, or 8 with
:>4 x 1 MB. Too much, or not enough! Twelve seems about right;
:>32-bit brouhaha notwithstanding, it seems a reasonable amount for a
:>16 MHz '030. Is this possible?
:>
:>-- Bill (johnston@minnie.me.udel.edu)
According to the latest (July) MacWorld and MacUser, only the IIsi and the
LC can address 2 meg simms. Must have something to do with the ROMs.
Cheers,
Alan
--
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Alan R Fry | You know what I hate?
afry@uhura.cc.rochester.edu | Rhetorical questions
--------------------------------------------------------------ccjapu@uta.fi (Jarmo Puntanen) (06/07/91)
In article <55485@nigel.ee.udel.edu> johnston@minnie.me.udel.edu writes: >Will the SE/30 or IIcx recognize 2 MB SIMMs? From 5 meg, it seems >that one has the option of going to 20 with 4 x 4 MB, or 8 with >4 x 1 MB. I thought the 24-bit ROMs in SE/30 limit you at 17Mb when using virtual memory, 8 without the virtual memory manager. IICx's 32-bit ROMs allow larger virtual memory pool, but the 8 Mb physical limit persists. Jarmo Puntanen/Tampere University Computer Centre, Tampere Finland.
johnston@oscar.ccm.udel.edu (06/08/91)
In article <2860@kielo.uta.fi>, ccjapu@uta.fi (Jarmo Puntanen) writes... >In article <55485@nigel.ee.udel.edu> johnston@minnie.me.udel.edu writes: >>Will the SE/30 or IIcx recognize 2 MB SIMMs? From 5 meg, it seems >>that one has the option of going to 20 with 4 x 4 MB, or 8 with >>4 x 1 MB. >I thought the 24-bit ROMs in SE/30 limit you at 17Mb when using virtual >memory, 8 without the virtual memory manager. IICx's 32-bit ROMs allow >larger virtual memory pool, but the 8 Mb physical limit persists. Some of the details may be inaccurate (SE/30 is limited to 14 virtual, and the IIcx has a 24-bit rom) but an interesting point was made about the "physical limit" of 8-meg. My understanding is that there IS a good reason for using >8 meg physical in a 24-bit-ROM Mac. With VM turned on, paging (swapping physical for disk-mapped RAM) should occur only when the limits of physical RAM are exceeded. Thus VM can be thought of as a way to take advantage of more physical ram, and not only as a trick to get extra address space by mapping the RAM to the hard-disk. True or false? Does the SE/30 have to actually move the data into the first 8 megs before it can be addressed by the CPU? What would be nice is a virtual memory implementation that ropes off the extra disk space only if available physical RAM is less than the requested virtual RAM. That would make 16meg SE/30's reasonable, and I am sure that somebody could think of a way to use the 16-14=2megs leftover as a RAM disk. The DOS world is full of hacks like that. -- Bill (johnston@minnie.me.udel.edu)
Ian_Pennington@mindlink.bc.ca (Ian Pennington) (06/12/91)
bill.... if you can get the simms, it should work. Here's the problem: the mac system software (up to 6.07) only recognized 8 megs of ram If you had a nubus machine (ie: mac II or higher), there is software available called "Maxima" that allows the system to fake one additional meg per empty nubus slot. Anyway, the se30 has 8 simm slots, you could put 8 1-meggers into it regards...... Ian Pennington