Conference 7.286::macintosh

    I wasn't sure where to put this...
    
    How do I install memory in a PowerMac 8500 ???
    
    With the recent Apple price cuts, I decided that it was time to upgrade
    from my old 660av to something faster (besides, the games run better -
    OK, it was Dark Forces and my wife will not let me use her PowerCenter
    132 long enough to have any fun - she says she has work do to :-)  So I
    decided that the price point/performance curve on an 8500/180 was just
    right and I picked up one from ComputerTown (Nashua, NH) yesterday at
    lunch.
    
    Now I want to upgrade the memory from 32MB to at least 64MB (My wife
    has 64MB and I don't want to be behind the memory curve with respect to
    my wife :-)
    
    But the insides of the 8500 only make adding PCI cards easy, and adding
    a extra disk is almost easy.  But messing with memory and VRAM and the
    Cache card appear to be a major "Disassemble" job, plus the owners
    manual says "No Disassemble!"
    
    So, does anyone have experience with installing more memory in an 8500
    that would like to give me some instructions.
    
    Thanks.
    
    					Bob Harris

I did this once. I can't seem to find instructions. It *is* a major 
disassembly job. Start with Appendix B of the User's Guide. At around about 
step 5 (for PCI cards), you'll see one card already in there (processor 
card?). I seem to recall removing that. On the other side of the box, the 
big card, which I think is the logic board, also has to be removed to access 
the DRAM slots (I don't recall if they are on that or hidden by it). To 
accomplish that, you have to disconnect a set of plugs along its top. 
They're mostly small and hard to get at. The good news is that several of 
those will continue to work even if you break off various pieces when 
putting them back (or so I've heard ;^).  After they're disconnected, the 
logic board will seem to be solidly in place. Don't be intimidated: work it 
out. Instructions for installing the memory chips and where are in the 
User's Guide, but the instructions in the "Technical Information" booklet 
are fairly complete. Once the chips are in, you just have to reseat the 
logic board, reconnect those damned plugs, get the processor card back in 
and reconnected, put the retainer back, and wrestle with the case to get it 
back in place (don't be afraid to bend those foolish metal tabs if they get 
in your way at this step :^)

I did this with a Digital-owned system, with a hardware tech turned software 
engineer looking over my shoulder. If it were my money invested, I might 
very well consider taking Apple's recommendation to heart and letting a 
professional have a go at it (the cost will still be just a fraction of what 
you'd have paid for the memory a year ago, and your warranty will still be 
in effect). Now, if you want to think disk drive instead of memory - you 
could probably get a second drive in there in 10 minutes with your eyes 
shut.

I'd let you practice on my system, but it walked away soon after getting a 
2nd disk drive.

From notes in this conference, it appears that a 256k level2 cache makes
a significant performance boost.  

Can someone explain a level2 cache actually is and does it really seem to
help?  I have a 7200 mac.  How can I tell if I have any level2 cache already?
Is this something you install yourself fairly easily?  Suggestions
on a good place for ordering it....


thanks,

mike

    re: .218, 219
    
    I went through this pain about a dozen times so far on an 8100/110, an
    8500, and 9500. As yet, I haven't killed any parts and I'm hardly an EE.
    
    The most frustrating part to me is the amount of force necessary to
    insert PCI cards--seems to be twice the amount that was needed for
    NUbus. AT the point I'm sure the motherboard or display card is going
    to crack apart, it finally slips in. I sure wish I could have bought
    one of the new easy access 9600's instead of the 9500.
    
    My work 8500 has a screw which holds the logic board and plastic board
    clasp in place. I would also warn you about the powered-on LED which is 
    90 degrees from the row of connectors along the top edge. It's easy to 
    forget about this.
    
       erik

    
    I installed a level 2 cache in my 7200, I went with a 512K level 2
    cache, it was not much more. There is a difference in speed, I posted
    some comparisons in this conference (in the inkjet note I think) and
    someone without the cache posted their numbers. Mine is a 7200/75 and
    it compared favorably with a 7200/90 without cache.
    
    A level 2 cache extends the processors built in cache. It is different
    from a RAM cache that can be set up in the Memory Control Panel (aka
    Disk Cache). It is faster and it is searched second (the internal
    processor cache (32K in the case of the 601 inside the 7200) is
    searched first).
    
    It's very easy to install the level 2 cache SIMM on the 7200. I
    installed the L2 SIMM, 2 memory DIMMs, and filled up the VRAM slots
    (can't remember if it was 3 or 4 VRAM SIMMs) in less than 10minutes.
    Everything is very accessable on the 7200...it's a well designed box.
    
    I'll try to find where we did those comparisons so you can take a look.
    
    Mario

    
    RE: 7200 caches
    
    the notes were 596.273 and 596.276 (others in that area may interest
    you. Here are some clippings from those notes;
    
    7200/75Mhz/32mb RAM/512K Cache/640x480 @ 256 Colors/4mb internal VRAM
    
                            All inits       No Inits        All but HP
        Processor           15.22           15.58           15.30
        Floating Point      13.11           13.28           13.18
        Disk Mix            15.78           16.41           15.87
        Graphics Mix        20.78           19.31           21.39
    
    PowerMac 7200/90Mhz, MacOS V7.5.3 rev. 2, 16Mb RAM, no L2 cache, 128K
    cache configured in memory ctrl. panel, 1Mb VRAM...   Virtual memory is
    on, when RamDoubler is disabled.  Display is 832x624 @ 16bits depth.
    
                     None   All    All but     All but   All but  All but
                                   7200 Video  RamDbl    HP       HP & RamDbl
       
    ----------------+-----+------+------------+--------+---------+------------+
    Processor        12.92  12.69   12.74       12.70    12.68    12.75
    Floating Point   14.18  14.00   13.98       13.93    13.97    13.84
    Graphics Mix     10.74   8.95    7.83        9.05     8.78     8.92
    
    
    Mario
    

    Re: .219 (Lee Clark) and .221 (Eric Goetze)   
    
    Thanks.  I managed to get access to the Motherboard last night.  Your
    instructions, warnings, and encouragement helped a lot.
    
    ----
    
    I took notes and here is what I did (minus my mistakes :-)
    
    NOTE:  I suggest using a Grounding Strap to prevent static discharge. 
           If a static strap is not available, get one from Radio Shack. 
           If that is not an option, then don't work in a static
           environment, and always touch the metal frame in the case before
           touching any electronic components or wires so you don't ZAP the
           system.  Have a nice day :-)

    o  Remove the 4 cover screws at each corner on the back of the system.

    o  Slide the cover back an inch and then lift it off.  The initial
       sliding may be stiff so just work it around a little.

    o  Looking at the system from the front, you will see on the left side
       the PCI card retaining bracket.

       Pinch the top sides of the bracket together.  Pull it out and swing
       it down on its hinges.

    o  Remove any PCI cards (I don't have any, but Eric says they can be
       stubborn). 

    o  Remove the CPU Daughter card.

    o  Remove the Audio/Video ribbon cable that plugs into the motherboard
       just under the CPU Daughter card.

    o  Now switching to the Right side of the system, gently remove the
       plastic Power On/Power Off/Power On LED bracket. 

       There are 2 plastic tab/clips that attach the bracket to the case.

    o  Remove the Power On LED cable from the motherboard.

    o  Remove the cables along the top edge.  There are 7 plugs.  The 2
       plugs with the heavy duty wire bundles have a locking clip on the
       back.  Make sure you press the clip to unlock it before pulling.

       NOTE:  DO NOT pull on the wires, instead pull the plug.  The power
	      wires are just crimped into the plug and are not always as
	      solidly attached as one would like.  I'll tell you a story
	      later :-)

    o  Remove the philips head screw in the center of the motherboard.  It
       can be found in a recessed (counter sunk) hole in the plastic frame
       that is covering the motherboard (I didn't see it at first and
       couldn't figure out why the board would not move).

    o  Now the motherboard should move easily.  
    
    o  Slide the motherboard towards the front about a 1/4 inch so that the
       plastic retaining clip on the upper left side of the motherboard is
       centered in the motherboard notch provided for the clip.  
       
    o  Now lift the plastic retaining clip on the upper right edge of the
       motherboard to free the board.

    o  Swing the motherboard down and remove.

    The DIMM, the Cache, and the VRAM sockets are now available for
    upgrading. 

    To put it back together, just reverse the process.

    ----

    Side story.  I was very careful about doing the above steps, but after I
    had put everything back together, the system would not boot.  "Woo is me"
    I've had the system for a day and a half and I've broken it :-(

    I tried several things, and retried stuff, but not luck.

    Finally I started to take the system back apart and check everything I
    had done.  
    
    As I was removing the large power plug from the motherboard, I noticed
    that the yellow wire was broken off from the other end of the cable (the
    end that plugs into the power supply).

    After looking at it more closely, I discovered that the wires are just
    crimped into the plug.  
    
    Looking closely at the hole where the yellow wire was supposed to be, I
    saw that the crimp didn't look as if it had been crimped tightly.  So I
    used a small screw driver and worked the crimp open a little more,
    striped some insulation off the yellow wire, put it into the plug, and
    then used the small screw driver to press the crimp into the exposed
    wire.

    All better.

    My Mac was alive again.

    So the moral of the story is, do not pull on the wires.  They are not
    really all that tightly attached to reality.

					Bob Harris

>     <<< Note 46.218 by UNIFIX::HARRIS "Juggling has its ups and downs" >>>
>              -< How do I install memory in a PowerMac 8500 ??? >-
>
>    I wasn't sure where to put this...
>    
>    How do I install memory in a PowerMac 8500 ???

Apple has always said that installing memory is a service tech job that,
if improperly done, will void your warranty.  Balderdash!

The Chip Merchant web pages include pictorial instructions on adding
memory for lots of processor models.  I can't get there right now
to find just the right page, but their top home page is 
    www.thechipmerchant.com    (don't forget the "the")

I used their instructions to upgrade my 7100 in a somewhat nonstandard,
reduced disassembly way.

- tom]

    Re: .225
    
>    The Chip Merchant web pages include pictorial instructions on adding
>    memory for lots of processor models.  I can't get there right now to
>    find just the right page, but their top home page is
>    www.thechipmerchant.com    (don't forget the "the")
    
    Thanks for the tip.  However, the only thing on their web site about
    the 8500 is a picture of the motherboard, but nothing on how to get
    access to the motherboard.
    
    I do use The Chip Merchant for memory, but I have my bookmark set to
    take me directly to the price page, so I don't see all the other stuff
    and I didn't even think to look.
    
>    Apple has always said that installing memory is a service tech job
>    that, if improperly done, will void your warranty.  Balderdash!
    
    I can see Apple's point for the 8500, but I do agree with you also.  In
    the case of the 8500, it is a few steps above just opening the case and
    plugging in the SIMMs/DIMMs.  With all the things to unplug and unclip
    and unscrew, it is easy to miss something and damage a component.  If
    it wasn't for Lee's and Eric's advice, I might have made a mess of
    things.
    
    The good news is that the 8600 will have an easy open case and easy
    access to all components.  Apple swings from hard access (original Mac)
    to easy access (Mac II series and some of the performas) to hard access
    (the 7100, 8100, 8500, 9500) to easy access cases (8600, 9600), etc...
    
    					Bob Harris

    hard/easy/hard/...   7200 is the easy access type ;-)
    
    I would have thought the whole 7*00 series had the same easy access
    case that unfolds itself like butterfly wings.
    
    I bet Apple will have to make a choice quickly enough: PowerComputing
    choose the easy way for all his machines, and I guess the other Mac
    compatible vendors did it as well (who knows about Motorola, Umax,
    DayStar,... models?).
    
    	-- Ol.