Conference hydra::amiga_v1

    I have a 2000 and am considering adding Fat Agnus and a SupraRam
    2000 with 2meg.  What should I be looking at to have FA installed
    in my system by a dealer? or can it be installed without hassle
    by myself?
    
    

Re: .1

Poke around in the notesfile: there are several descriptions of installing
the Fat Agnus.

I elected to have my dealer do the upgrade because:

	1.  The Agnus is a hard chip to remove.

	2.  You have to cut a trace on the motherboard.  (I don't like
	    making irreversible changes to my system.)

The Agnus is a large square chip that sits down *inside* of a special
square socket.  Getting the Agnus out is a challenge, and a a clumsy
attempt will destroy the old chip and ruin the socket.  (A popular
method of removal was to remove the entire motherboard and push the
Agnus out of its socket from underneath.)

    
    I don't know about you, but if I were to upgrade my fat Aggie,
    I'd wait a little.   My dealer told me that the one comming 
    with the release of WB2.0 (along with some other chip) will
    be able to address 2 meg.  He said that the chip is different
    and the whole upgrade for a A2000 (WB 2.0 + all required chips)
    will be in the area of $160.00 (US)
    
    I have the 1 Meg one and I will upgrade to the 2 meg if someone
    can prove that WB2.0 can run my programs (DPaint3 etc...)
    
    BTW: I paid $90 (US) for my Super Fat agnus. It was a pain
         to install without the chip removal tool.
    
    Vince.

>    I don't know about you, but if I were to upgrade my fat Aggie,
>    I'd wait a little.   My dealer told me that the one comming 
>    with the release of WB2.0 (along with some other chip) will
>    be able to address 2 meg.  He said that the chip is different
>    and the whole upgrade for a A2000 (WB 2.0 + all required chips)
>    will be in the area of $160.00 (US)
    

Unfortuenatly, the 2 meg Agnus only works in the Amiga 3000. There
is an extra address line there that the 2000 does not have on the mother
board socket. Commodore (the guy who designed the stuff) says it's a major
hack to get one on the 2000.

john

Re: .3, .4

Actually, if you have the one meg Agnus, you have the two meg Agnus,
but in order to use it in two meg mode, you would have to cut open
it's plastic casing, solder a new connector to the enclosed chip,
add another address line to your motherboard, and install another
meg of memory.

Let me explain:  Most of an integrated circuit is its plastic shell
with the pins coming out of it.  The actual silicon chip inside
is much smaller.  The job of the plastic shell is to connect the
small, delicate leads on the edge of the silicon chip to the sturdier,
larger pins on the outside of the IC.  This makes the entire package
sturdy enough that you could insert it an remove it from a socket,
and large enough that a human could actually work with it (like solder
a wire to a pin.)

Commodore knew that they wanted an Agnus that could manage two meg of
chip ram.  So they designed it.  However, they had a problem:  The
Agnus socket in the Amiga 2000 and 500 didn't have enough address
lines to address two meg of chip ram, and there wasn't two meg of
chip ram on the motherboard anyway.  The solution was to take two
meg Agnus chip and put it in a plastic shell so that it would fit
the Amiga 2000 and 500 Agnus sockets.

So, the two meg Agnus has been shipping for almost a year now.  It's
just that it has been crippled into a one meg mode by the plastic
package surrounding the silicon chip.

    Hi John,
    
    Re: -.1
    
    You're probably right,  my dealer only "saw" a A3000 and WB2.0.
    
    Like I mentionned before, I just repeat what he told me.
    
    I am sure some hacker will get the 2 Mg Fat agnus to work on
    a A2000.  I'll try anyway.  Can't wait...
    
    Vince,

Randy, is there a 'jumper' in the chip that says "but you don't have that extra
address line" or can you tell it it has 2 meg and it overlaps the 1st meg?

john

Re: .7

I suspect that there might be something special that is done when
packaging the chip for a one meg system instead of a two meg system:
it seems to simple for it to just be don't connect pin 73 to the
chip.  But I don't know.

    Don't you guys watch TV???  I saw a movie (the icredible journey if my
    memory serves me right) in which they did pop open a chip and fixed it
    with the tools they had (microscope, tweezers...) and it WORKED!!!
    
    Jean
    

    Hi,
    
    I just checked out my A2000. It's a German Rev4.0 board WITH A
    RECTANGULAR AGNUS!!!!!! Help! Does this mean that I canna get a new
    (improved biological) agnus?
    
    Dave.

Re: .10 COMICS::HOGGAN

	If your Agnus is indeed in a rectangular dip package and not a square
package then you may have to replace your mother board to upgrade to the new
ECS chip set.  I would suggest waiting until you can get the new motherboard
with all of the ECS and V2.0 ROM before ordering it.  This could save you from
replacing chips on the new motherboard at additional cost...

-----Robert

    Hi,
    
    Arrrrgggh? Replace the motherboard? I'm frightened to ask, but How much
    will this be? (I don't think I'm gonna like the answer!)
    
    Dave.
    

    I recently had to have my rev 4.5 motherboard replaced. The total
    cost was about $250 plus the old board. This is not a bad deal when
    you consider that the new board COMES with KS 1.3 and the fatter agnus
    (which cost about $150 on their own). I lost out in that my old
    board already had these chips and CBM offers no reduction in price
    for this (I wished I had saved the old chips and exchanged them
    ahead of time).
    
    I have no idea how this will be different for an A2000 motherboard.
    If I remember correctly, a direct purchase of a motherboard is about
    $900.
    
    Keith