Conference hydra::amiga_v1

    My solution to problems of this class would be to go to a dealer and
    tell him I wanted an A500 with 1 MB of chip RAM.
        John Sauter

    Re .0:
    
    The size of CHIP RAM may or may NOT be a constraint to the use of one's
    A500.  Certain types of applications, especially drawing programs that
    support artwork with LOTS of bit planes, gobble CHIP RAM like candy. 
    Productivity (word processing, spreadsheets, et al) tools tend to need
    raw memory and would best use a configuration with lots of FAST RAM.
    
    I have a new A500, but I haven't yet determined which Agnus is in it. 
    My priorities call for me to add at least another 1MB of FAST RAM
    before I start worrying about exhausting CHIP RAM.  My belief is that
    the system isn't really "in balance" until it has at least 2MB of RAM
    (of whatever type).
    
>   I've been told by some people that if the amiga 500 I have is  equipped
>   with the fatter agnus, all that I would need to do in order to get 1
>   meg of chip ram is add a 512k expansion board and cut a couple traces
>   on the expansion board.
    
    I've heard that also.  I can't imagine NOT having the A501 (or its
    equivalent) clock/memory expansion board, anyway.  I'm sure there are
    LOTS of caveats that go with this simple statement.
    
>   Other people that sell expansion memory boards tell me that any memory
>   that is added to the system is FAST memory. Who's right?
    
    The second 512KB is treated like FAST RAM for allocation purposes, but
    it has the same speed as the CHIP RAM.  You'd might as well call it
    "HALF FAST" RAM, because that's how it runs.  See what a half-truth
    gets you?
    
    Bottom line:  if you're obsessed with having 1MB CHIP RAM from the
    outset, don't fool with the A500.  Go directly to an A2000 (Omnitek had
    a stack of A2000HD systems at $1800 on Saturday -- certainly worth
    checking out! 8^) and get the other benefits that come with it.

Re: .0

>   I've been told by some people that if the amiga 500 I have is  equipped
>   with the fatter agnus, all that I would need to do in order to get 1
>   meg of chip ram is add a 512k expansion board and cut a couple traces
>   on the expansion board.

>   Other people that sell expansion memory boards tell me that any memory
>   that is added to the system is FAST memory. Who's right?

There are two different types of memory expansion here.

The Amiga 500 has two expansion ports.

The first port is accessed by opening a panel on the bottom of the 500.
This expansion port is designed to accept only one thing: An A501
512K memory expansion/clock module (or any clones of the same made
by third parties).  This "expansion port" connects to the chip memory
bus.  This memory is "half fast" memory without the new 1 meg Agnus,
and chip memory with the new Agnus and appropriate motherboard
modifications.

The other expansion port is what is usually just called the "expansion
port" (catchy name, huh?).  This port is designed to interface to
Amiga 2000-style card cages, slap on the side memory expansions, or
slap on the side disk controllers (usually with optional memory expansion).
This expansion port is on a different system bus not accessible by the
custom chips.  When people talk about memory expansion, they almost
mean memory connected to this expansion port.  Thus "expansion memory"
is always fast ram, and can never be used as chip ram, even with the
new Agnus.

If you want one meg of chip ram, tell your dealer.  He'll make sure
the new Agnus is installed, cut the needed traces on the motherboard,
and sell you an A501 memory/clock module (which will always have to
be installed for the system to boot after it's been modified for 1 meg
chip RAM!).

Any Amiga 500 (past or present) can be modified for one meg of chip
memory by following the above.  Newer 500s just have the advantage
of already having the proper Agnus (an about $80 value).

    
    Info from the UINET Conference:
    
    All new A500's have had 1Meg Chip Ram Agnus's for some time, but
    they are of course disabled to 512KB.
    
    The part # on the Agnus chip for 1MB is 318069-02 (0 or 1 on the
    last digit were old 512KB for NTSC and PAL respectively).
    
    I have scanned through 9,000 topics today, but no one has actually
    described how we physically enable it ourselves (although everyone 
    says its simple - seems its a case of its OK if its someone elses
    machine but not on theirs). Most have recommended we get a service centre
    to do it (25$-30$ in US apparently). Apparently there is an article in
    Amiga Review in the last few months.
    
    Me? I'll bide my time a little longer and get a service centre to
    do mine when Super Denise comes out.
    
    Good luck.
    

    
    Excuse my ignorance but what is to cut couple traces. Secondly I
    recently got my 512k expansion which when I load WB redues it to
    838K. I`m thinking of expanding to 1m and was wondering how much 
    the chip would cost and could I put any (don`t shout) 1meg chip
    in.

    If you're saying it tells you you have 838K at the top of your
    workbench, then you already have 1 MEG of ram.  I assume you are saying
    that you don't have the 1 meg AGNUS.  (type AVAIL at the SHELL to find
    out.  It will tell you all the ram is in CHIP if this is true.)  I have
    seen kits listed in Amigaworld for the 1 meg kit, complete with chip
    puller and instructions.  Cutting traces means to cut the copper
    ciruits imprinted on the board so that it breaks the connection.
    
    Tony

    How old is your Amiga?  All Amigas built in the past year or so should
    have the 1Meg version of Agnus chip already installed.  But the A500
    motherboard is still configured to address only 512K Chip RAM unless
    you make circuit changes (by cutting etch paths).  The latest version
    of the A500 motherboard even has space for a second 512K of RAM chips,
    but I believe you must remove the "trap door" expansion in order to
    populate these.  The fatter Agnus chip sells for about $150 here in
    the states, if your machine doesn't already have one.

    Remember, Commodore does not officially support the configuration for
    1MB of Chip RAM on the A500 models.  You should not attempt doing the
    modifications yourself unless you are adept at soldering, etc.  A
    replacement motherboard will be very expensive!

    Also, there are a few programs around that do not like machines with
    no 'fast' memory.  It may be wiser to expand beyond 1Meg total memory
    before trying to maximize the Chip portion.  There's only so much you
    can do in 1MB, regardless of how it's distributed.