13 Replies Latest reply: Jul 18, 2011 10:32 AM by BDAqua
iCyphex Level 1 Level 1 (0 points)
Hello,

Which Ram do I actually need for my PowerMac G5?
Technical Specifications:

- 2x 2,0GHz
- Late 2005
- 8 ram slots

I want 12GB in total (5x2GB + 2x1GB)
Do I need SDRam? Normal Ram? So-DIMM?

Please tell me the exact kind of ram.
Thanks!

PowerMac G5 (late 2005), Mac OS X (10.5.8), Watercooled - 2x2,0GHz
  • japamac Level 7 Level 7 (24,390 points)
    For the dual core G5 RAM is up to a 2GB PC4200 DDR2 533MHz 240 Pin DIMM.
    http://eshop.macsales.com/MyOWC/Upgrades.cfm?sort=pop&model=234&type=Memory
  • romko23 Level 2 Level 2 (395 points)
    since 4GB is supported, could the G5 Quad and dual core expand undisclosed up to 32GB? 8X4GB chips? If the 2006 mac pro's was expandable to 16GB but OWC found a way to expand it up to 32GB, certainly the G5 Quad can also go up to 32GB undisclosed?
  • iCyphex Level 1 Level 1 (0 points)
    There currently are 444MHz modules in there.
    You sure it can run up to 533MHz?
  • old comm guy Level 4 Level 4 (2,235 points)
    iCyphex wrote:
    There currently are 444MHz modules in there.
    You sure it can run up to 533MHz?


    From the user guide:

    DIMMs must be installed in equal-sized pairs and fit these specifications:

    • PC2-4200, 533 MHz, Double-Data-Rate 2 (DDR2) DIMMs, also known as DDR2-533

    • 64-bit wide, 240-pin modules

    • 18 memory devices maximum per DIMM

    • Conform to JEDEC specification (see note below)

    • Nonparity

    • Error-correcting code (ECC) or no error-correcting code (NECC) modules. Do not mix
    ECC and NECC memory modules within a pair.

    • Unbuffered (not registered or buffered)

    • Maximum height of 1.25 inches

    Important: DIMMs from older Macintosh computers are not compatible with and do
    not fit in your Power Mac G5.

    Note: When purchasing DIMMs for use in Macintosh computers, make sure that the
    memory vendor conforms to the Joint Electron Device Engineering Council (JEDEC)
    specification. Check with your memory vendor to ensure that the DIMMs support the
    correct timing modes and that the Serial Presence Detect (SPD) feature has been
    programmed properly, as described in the JEDEC specification. To check the
    compatibility of your DIMMs, see the Macintosh Products Guide on Apple’s website at
    www.apple.com/guide.
  • japamac Level 7 Level 7 (24,390 points)
    There currently are 444MHz modules in there.

    Are you sure the machine is a Late 2005?
    Does the System Profiler identify the machine as a Powermac 11,2?
    You sure it can run up to 533MHz?

    Yes.
  • iCyphex Level 1 Level 1 (0 points)
    Yes, I am sure cause there currently are DDR2 modules in there.
    The late 2005 is the only one with DDR2. Older models did only support DDR(1)
  • japamac Level 7 Level 7 (24,390 points)
    Is the 444 MHz as reported in the System Profiler?
    If so, it is likely that the RAM is faster, but due to the programming of the EEPROM, the speed is incorrectly reported.
    This is a common occurrence with RAM that is faster than 533 MHz.
  • iCyphex Level 1 Level 1 (0 points)
    _2 Gb DIMM DDR2 4200 533mhz_
    http://bit.ly/egCymH

    Will that one do it?
    Is SDRAM required?
    or will normal ram do it.
  • BDAqua Level 10 Level 10 (120,655 points)
    Going by this on your link...

    This memory is designed for the following systems: Apple iMac G5 17-inch 1.9GHz (iSight) (DDR2); Apple iMac G5 20-inch 2.1GHz (iSight) (DDR2).


    Cross checking here...

    http://eshop.macsales.com/shop/apple/memory/iMac/G51.9GHz_2.1GHziSight

    2.0GB (2048MB) PC4200 DDR2 533MHz 240 Pin DIMM Module for the Apple iMac G5/1.9GHz, iMac G5/2.1GHz Models, PowerMac G5 'Dual Core' Models (pairs required for PowerMac)...


    Looks like the same RAM is used for the Dual Core G5 Powermacs.
  • japamac Level 7 Level 7 (24,390 points)
    Will that one do it?

    Yes.
    Is SDRAM required?

    Yes.
  • iCyphex Level 1 Level 1 (0 points)
    Thank you. I've ordered my modules
  • Dan Lempesis (Omega) Level 4 Level 4 (2,420 points)

    Sorry to dig up an old topic, but I have some similar inquiries.. I've been trying to find out if the G5 can actually support more than 16 GB RAM. You say it can support 4 GB modules.... thus the limiting factor might be the memory controller's inability to address > 16 GB.

     

    Also, DDR2-667 and 800 areactualy cheaper than DDR2533 these days. Would it be reasonable to assume that if I bought a DDR-667 or 800 module, it would drop to 533 speeds and maybe even to a lower CAS latency... say CL3-3-3?

     

    Thanks.

  • BDAqua Level 10 Level 10 (120,655 points)

    Hi Dan,

     

    >Would it be reasonable to assume that if I bought a DDR-667 or 800 module, it would drop to 533 speeds and maybe even to a lower CAS latency... say CL3-3-3?

     

    If it worked in a Mac, then yes you'd expect lower CAS from "faster" RAM.

     

    Never heard of anyone going more than 16GB in a G5.