MacBook 2.4 won't start after 4GB upgrade

Discussion in 'MacBook' started by keithtm, Apr 3, 2008.

  1. macrumors newbie

    Joined:
    Apr 3, 2008
    #1
    had a search through the forum to no avail.

    i have 2 new 2GB sticks (rated at 800Mhz). when i put them both in the machine, it won't boot past the black screen.

    when i use either of them with either of the old 1GB sticks in either slot, system boots to 3GB no problem.

    tried resetting PRAM, NVRAM and SMC but all to no avail.

    difficult to understand whether the problem is with the machine or the ram - any suggestions?

    thanks
     
  2. macrumors 65816

    Jiddick ExRex

    Joined:
    May 14, 2006
    Location:
    Roskilde, DK
    #2
    It's 99% RAM related.

    Does it start with 3GB regardless of which new stick you are using?
     
  3. macrumors 6502

    Joined:
    Apr 12, 2007
    #3
    Do both sticks work on their own (ie without the other 1GB added)???
     
  4. macrumors 6502a

    MacHiavelli

    Joined:
    May 17, 2007
    Location:
    london
  5. macrumors 65816

    Jiddick ExRex

    Joined:
    May 14, 2006
    Location:
    Roskilde, DK
    #5
    They should in theory take 800 mhz and downclock it to 667mhz but the new SR platform with a Penryn CPU has some problems using these (which CanadaRAM can explain much better than I can).

    It might very well be because of the 800mhz that the OP is experiencing problems.

    Why did you even buy 800mhz RAM in the first place? Wanted to use more money? :)
     
  6. macrumors 65816

    Joined:
    Mar 24, 2008
    Location:
    Winnipeg
    #6
    yea its sopposed to be 667mhz ddr2 sdram well at least in my computer
     
  7. macrumors 65816

    Jiddick ExRex

    Joined:
    May 14, 2006
    Location:
    Roskilde, DK
    #7
    It's supposed to in all portable Intel macs. No logic boards support 800mhz. That said, in theory the logic board should downclock the RAM to 667mhz no problems.
     
  8. macrumors 6502a

    riscy

    Joined:
    Jan 4, 2008
    Location:
    China
    #8
    If as some people say, that speed will run on your MB (I dunno), check that you have pushed it in far enough - I just upgraded my RAM last weekend and really had to push it in to get it to house properly in the settings.

    It took more oomph than I expected, it does not just glide in.
     
  9. thread starter macrumors newbie

    Joined:
    Apr 3, 2008
    #9
    the memory was the same price as 667 ram. since it appeared too-fast-ram wasn't a problem, that it would just run it at 667, i thought there should be no problem.

    i didn't think of trying just a single stick. i'll let you know how i get on.
     
  10. macrumors G5

    CanadaRAM

    Joined:
    Oct 11, 2004
    Location:
    On the Left Coast - Victoria BC Canada
    #10
    There is a well-known problem with 800 MHz memory not having properly written SPD values and being incompatible with Penryn Macs. So although theoretically they should clock down to 667, if they are not programmed properly, they won't work. One report is that they do work when installed one at a time with an Apple RAM in the other socket -- because the Apple RAM forces the machine to 667 CL5 timings with its correctly written SPD values. But with only 1 or 2 of the 800s it fails.

    A case of false economy -- the 'faster' RAM gives you no speed benefit plus added grief.

    MR Guide to Buying RAM

    The other issue with MacBooks that is very common: not installing the RAM completely. When you push the RAM into the slot, it goes in about 1 inch and stops. It is not installed yet. You need to get both thumbs on the RAM and push hard, and it goes in another 1/8" or so (2mm for the eurocentric SI crowd. Here in Canada we're informally bimetric as well as legally bilingual. Or maybe that's polymetric. Can't remember)

    Anyway, if you don't have dents in your thumbs, you haven't pressed hard enough.

    The classic non-inserted RAM symptom is a pulsing white power light and a black LCD screen.
     
  11. macrumors 68040

    RedTomato

    Joined:
    Mar 4, 2005
    Location:
    .. London ..
    #11
    where did you get your ram from, and which brand is it?

    Like the other posters, aye, its 99% sure to be an issue with your new ram.
     
  12. macrumors 6502a

    mlemonds

    Joined:
    Apr 9, 2008
    Location:
    Lexington, KY
    #12
    Did you try the ram in another computer?

    could be some DOA ram. (something that only pops up when running dual channel)

    just a stab in the dark

    no brand is perfect.
     
  13. macrumors 6502a

    Joined:
    Mar 23, 2008
    Location:
    Brooklyn, NY
    #13
    Umm, it's always a good idea to install RAM that adheres to the specs established by the manufacturer, which in this case is NOT 800Mhz. So, if you ignore the specs and then have a problem, most people would suggest that as Troubleshooting Move Number 1 you use components that comply with the specs.
     
  14. macrumors demi-god

    xraydoc

    Joined:
    Oct 9, 2005
    Location:
    192.168.1.1
    #14
    Its not only Penryn Macs that have this issue - virtually any Mac on which you try RAM modules with incorrectly programmed SPD codes will fail. There's no BIOS to override the SPD code, so if the boot firmware can't read the SPD timing, it won't boot. This is why it'll work with one proper and one improper module - at least one module has proper timing codes.

    Return the chips, buy Mac-tested RAM.
     
  15. macrumors newbie

    Joined:
    Apr 8, 2008
    #15
    Very informative, CanadaRAM. :)
     
  16. macrumors newbie

    Joined:
    Apr 12, 2008
    #16
    Memory Issue

    I purchased Corsair Gaming Memory with the 800mhz. The reason I did was because I have always been under the impression that matching the bus speed on the computer will get the best performance. and since the macbook pro has a bus speed of 800mhz. enough said. I am able to use one 2gb stick of corsair gaming memory, and one of the 1gb sticks that came with the laptop making it 3gb of memory. if I put both 2gb sticks I just get the black screen. and it won't go on from there. I know its been mentioned before about the memory being an issue, but if it works with one stick, why not both? thanks for the help.
     
  17. macrumors 68040

    Joined:
    Jan 15, 2008
    Location:
    Holocene Epoch
    #17
    This has to be the best MacBook memory upgrade advice ever. :)
     
  18. macrumors 6502a

    Joined:
    Mar 23, 2008
    Location:
    Brooklyn, NY
    #18
    So you thought that 800Mhz memory gave better performance in the Mac than the RAM that Apple recommended but that Apple decided to hide that fact?
     
  19. macrumors newbie

    Joined:
    Apr 12, 2008
    #19
    Memory Issue

    It is all hardware, it is just mac operating system, and windows operating system, its still hardware for memory. when building computers, matching the memory and the front bus is the best way to get the best performance. And of course Mac wants you to use Mac approved memory, its made from samsung, and Mac makes so much money off of it. but it doesn't matter what memory, its about the hardware, cause what makes Macs a Mac is the operating system. I think I mentioned Hardware a lot here.
     
  20. macrumors demi-god

    xraydoc

    Joined:
    Oct 9, 2005
    Location:
    192.168.1.1
    #20
    But you forget that the "hardware" in the MacBook, despite using an 800MHz FSB in the Santa Rosa revisions, use only a 667MHz memory bus. Period. There is no 800MHz support. And there's no BIOS in which to attempt to overclock it to 800MHz.

    You can (try) to put 500THz RAM in to the machine, but it'll still only run at 667MHz in the MacBook (and MBP, iMac and Mac mini).

    In your post a few lines up, you speak about one 800MHz stick and one Apple stock stick working, but not both 800MHz sticks. The reason, as we've said, is because its only running at 667MHz - set by the stock Apple DIMM. The faster RAM isn't supply proper 667MHz-mode SPD codes to the Mac's firmware, so it fails to boot.
     
  21. macrumors 68040

    RedTomato

    Joined:
    Mar 4, 2005
    Location:
    .. London ..
    #21
    Wow. Epic fail.
     
  22. thread starter macrumors newbie

    Joined:
    Apr 3, 2008
    #22
    wow you guys are very passionate, but not so good at reading usernames.

    wish i'd seen the thing about the apple not liking faster ram. i'd only read about the fact that faster memory should be capable of running slower.

    i'll live with 3GB for the price i paid, and share a little memory love with my gf's macbook.

    thanks for all the advice!
     
  23. macrumors demi-god

    CWallace

    Joined:
    Aug 17, 2007
    Location:
    Seattle, WA
    #23
    Your problem is not so much using "faster RAM" (I use 800MHz RAM in my iMac and MacBook that runs at 667MHz in both units), but that the RAM you purchased is not able to be properly configured for running at the 667MHz speed your MacBook runs it at.

    I would recommend, if possible, returning both sticks and choosing another supplier. I use Crucial, for example.
     
  24. macrumors newbie

    Joined:
    Apr 12, 2008
    #24
    Memory

    Red Tomato, wow, very funny. no I don't mean to sound defensive. at all. for the record, the sticks were just bad, and when I replaced them they work fine.
     
  25. macrumors G5

    CanadaRAM

    Joined:
    Oct 11, 2004
    Location:
    On the Left Coast - Victoria BC Canada
    #25
    Umm.. right. And the Hardware has a 667 MHz memory bus.


    For next time, have a look in the MacRumors Guides, under the Guides tab at the top of the window

    Guides: Hardware: Understanding Intel Mac RAM
     

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