Is there any chance of this RAM working in my 8500?

Discussion in 'Apple Collectors' started by bunnspecial, Dec 7, 2014.

  1. bunnspecial macrumors 603

    bunnspecial

    Joined:
    May 3, 2014
    Location:
    Kentucky
    #1
    I gutted a couple of c.1998 workstations at work a few weeks back that were headed for surplus. To give some idea of what I was dealing with, each system had 4 Pentium II Xeons, and 16 sticks of RAM.

    I thought that the RAM was standard PC-66 or 100, but won't fit into sockets designed for this RAM.

    The sticks are all 168 pin DIMMS. As per some specs I found from Googling the numbers on the stickers, these are 50ns FPM/EDO 4K and are 128mb each. This seems to compare favorably with the specs OWC lists for this system-the memory they sell for the 8500 is 60ns(or a little slower than what I have), and is also EDO.

    I have two potential concerns-the RAM that I have is ECC, and it's also taller than what OWC sells(1.25" vs. 1.15").

    All of that said, is there any chance of it working in my 8500? Since I have 32 sticks of this stuff, I'd really like to be able to use it rather than having to buy RAM for this computer. If it would work, that would give me enough RAM to max out both my 8500 as well as my future(intended) purchase of a 9600.

    Any thoughts on this?
     

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  2. tdiaz macrumors 6502

    Joined:
    Feb 7, 2006
    #2
    If the DIMM physically fits in the 8500.. it will work. The location of the keyways changed ever so slightly in that era.

    The difference of positioning is about 1 pin on the edge connector. It may look like it fits, but if you can't snap it down without resistance, it's not going to actually go in.
     
  3. bunnspecial thread starter macrumors 603

    bunnspecial

    Joined:
    May 3, 2014
    Location:
    Kentucky
    #3
    Thanks...looks like I'm going to have to bite the bullet and take the logic board out of the thing to find out(a job I'm not looking forward to).

    As I said, I know that it won't fit in a PCC-66/100/133 slot. It looks like it should, but will not physically snap in. I suspect that the difference is-as you've said-one contact in one of the keyways.

    I really wish that I could find a high-res picture of the proper RAM so that I could count the contacts and see if this is the same.

    The thought of 1gb of RAM in my 8500 is exciting.
     
  4. MacTech68 macrumors 68000

    MacTech68

    Joined:
    Mar 16, 2008
    Location:
    Australia, Perth
    #4
    According to the 7500/8500 developer technotes, the maximum height is 31.88mm or 1.255 inches. Yours are 31.75mm so they will likely place pressure on the logic board once installed - not a good idea.

    Also, that DIMM you have is 3v EDO. It will not work in the 8500 which requires 5volt FPM.

    At the time, Apple says the largest DIMM is 128MB, must be installed in pairs, and the maximum total is 1GB.

    Sorry, but I don't think these will work.
     
  5. bunnspecial thread starter macrumors 603

    bunnspecial

    Joined:
    May 3, 2014
    Location:
    Kentucky
    #5
    Thanks-looks like I just need to break down and order the proper stuff from OWC.

    I'll probably just order 4x128, as I can't imagine what I would do with thus computer that would require more.
     
  6. MacTech68 macrumors 68000

    MacTech68

    Joined:
    Mar 16, 2008
    Location:
    Australia, Perth
    #6
    Just noticed my mistake on calling them too tall. They are actually shorter than Apple's quoted maximum. :eek:

    Regardless, they are 3V EDOs which for most of Apple's Early PCI PowerMacs (601 and 604 CPUs) have been quoted as being possible to damage the motherboard.

    There is one model that CAN take EDO - not sure if 3v works and I can't remember which model. Probably the 4400/7220 Motorola boards but don't quote me on that.
     
  7. orestes1984, Dec 10, 2014
    Last edited: Dec 10, 2014

    orestes1984 macrumors 65816

    Joined:
    Jun 10, 2005
    Location:
    Australia
    #7
    The locations on the pins on the RAM are different, the 7600 and 8500 will not fit standard RAM like later model Macs. None the less it should be cheap and easy to find Mac specific RAM. I've been through this myself. The maximum capacity RAM chip it will handle is 128mb per stick using 70ns 168-pin DIMMs. There are 8 sockets onboard to fill for a total of 1GB of RAM.
     

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