Conference hydra::amiga_v1

    The 8-Up was originally available only in SIMM format, using the 256Kx8
    or 1Mx8 SIMM memory modules commonly used in recent Macintosh systems.
    (I have one of this type, love it!)  A "DIP" version was introduced
    later, it take regular 256Kx1 or 1Mx1 DIP chips like so many other RAM
    cards.  I assume the "(REVISED)" label means that the SIMM version has
    been updated in some way, this is the first I've heard about that.
    
    The SIMM version will probably cost a few bucks more to populate, since
    SIMMs tend to be slightly more expensive than individual DIP chips of
    equivalent size.  SIMMS are easier to install because each SIMM carries
    8 chips mounted on a single plug-in card, you won't have to worry about
    bending pins while inserting a chip, etc.

        While I can't speak for the Amiga upgrades, I prefer SIMMs over
        individual chips (dips) due to reduced handling involved and
        reduced interior space required by the SIMM module.
        
        Another advantage of the SIMM module is that due to the smaller
        physical size, the etch runs are shorter, thus providing a higher
        probabilty of the expansion memory actually working reliabily in
        your machine.
        
        Bob

Re: .7

Since note .7 was pro-SIMM, I thought I'd balance the discussion with
an anti-SIMM reply.

I prefer DIPs.  DIPs are cheaper.  You only upgrade a memory board
once or twice, and opening the machine and preparing a work environment
takes more time than inserting the chips in the board.  It isn't that
much more work to install 16 chips versus 2 SIMMs.

If you have a chip go bad, you can pull it off the board and
plug in a new one.  If a SIMM goes bad, you do the same, but
it will cost about nine or ten times as much (since you have
to throw away the good memory with the bad on the SIMM).

If you are getting a dedicated memory card, it doesn't matter
how big the card is (it will still take up one expansion slot).
So SIMMs more compact board layout isn't a real advantage.

As to whether a SIMM memory board is more reliable than a DIP memory
board because of shorter traces, I am unqualified to say.  However,
I'll make the observation that most Amiga memory boards are DIP,
and there doesn't seem to be much a a problem with memory boards
in general.

    An 8 Meg  256k x 1 is an awfully large board.
    I believe that SIMs consume less power than DIPs so bear in mind
    what your power supply can stand. !
    
    This Two Slot you speak of, does this mean that the memory board
    you are refering to is for an A2000 normally.
    Did you buy this ?
    
    
    			Pete
    
    

Re: .4

>    An 8 Meg  256k x 1 is an awfully large board.

All of the eight meg boards for the Amiga I've heard about use
megabit chips (or SIMMs based on megabit chips).  It's too hard
to get two hundred and fifty six 256k memory chips on one board!

>    I believe that SIMs consume less power than DIPs so bear in mind
>    what your power supply can stand. !

Is this true?  I believe SIMMs are just small daughter boards with
regular memory chips on them.  Thus, there is no power difference.

        I don't think SIMMs consume less power, but there would be less
        IR drop due to the shorter etch runs.
        
        As for physical size, the SIMMs do take up less space than DIPs
        because they are mounted on both sides of the module.  Cost wise,
        I bought mine for $92 each (1mb x 8) plus shipping about $6 for
        UPS blue.
        
        The adaptor card is much smaller as it only needs room for four
        SIMMs.  This may not be an issue for a 2000, but for more Atari
        ST it is important (no buss).  (yeah, yeah I know - boo, hiss...)
        
        Bob

	I believe that 8 x 1 Meg SIMMs are in fact small carrier cards 
with eight 1 meg x 1 chips on them.

	Is it possible to buy just the printed circuit carrier cards ? 
How much ?  From whom ?

	REG


		{"daughter boards"  is so sexist (-: }  

    When Microbotics introduced their original 8UP! board, they also
    offered what they called "PopSIMMs".  These are (were?) small SIMM
    cards with sockets for standard DIP RAM chips.  I don't remember
    the price, and don't know whether they are still available anywhere.