Memory help

Discussion in 'General Hardware' started by lancer, Jan 24, 2007.

  1. lancer

    lancer There is no answer! Political User Folding Team

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    ok so i eventually got my new system built, but i have an issue, i put 4gb's in 1gb sticks into my system, it supports up to 8gbs, the memory specifically is kingston hyperx, khx6400d2k2/2g, pc2-6400 (ddr2-800) and the mobo is an Asus P5W DH Deluxe.

    well all 4 sticks are in but it only shows 3.2gbs installed, it doesn't sound like a bad stick as that would probably show as 3.0gbs or less, i don't really understand the clock cycle info in the bios, anyone have any advice or help with this?

    thanks
     
  2. Aprox

    Aprox Moderator Political User

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    That sounds odd to me, but it could very well be a faulty stick. It might just be reporting an incorrect value. Have you tried updating your Mobo Bios? Moving the sticks around in the slots? Making sure they are all seated correctly?
     
  3. lancer

    lancer There is no answer! Political User Folding Team

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    updated bios, haven;t moved the sticks but i am going to replace one by one individually into the first slot and see if one is faulty...
     
  4. Aprox

    Aprox Moderator Political User

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    Sounds like a solid plan, report back to us what happens. Good Luck! :)
     
  5. NetRyder

    NetRyder Tech Junkie Folding Team

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    I'm guessing you're running XP SP2? :)
    You need a 64-bit OS to have the full 4 GiB of RAM available.
     
  6. lancer

    lancer There is no answer! Political User Folding Team

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    net, really? why is that?

    i'm runnign xp pro sp2.

    edit: didn't ms give xp 64bit away for free or am i day dreaming?
     
  7. Aprox

    Aprox Moderator Political User

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    That was a question I was going to ask but I didn't bother... was it reporting 3.2gb in windows or in Bios.
     
  8. lancer

    lancer There is no answer! Political User Folding Team

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    in both
     
  9. Aprox

    Aprox Moderator Political User

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    Ok, Net brought a very good point about windows, but if its reporting the wrong value in Bios then we know that the problem for now resides somewhere in the hardware. Any luck with your swap outs?
     
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  10. lancer

    lancer There is no answer! Political User Folding Team

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    i haven't tried it yet and cant until tomorrow as i have to use the machine tonight, i'll let you guys know in the morning, thanks aprox for you help and others.
     
  11. LeeJend

    LeeJend Moderator

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    Run CPUz tonight. It will give details on each memory stick. See if one reports wrong.

    But 3.2 GB sounds more like an issue with the value being reported by the stick or the bios than with a damaged stick or windows. 32 BIT Windows does support 4 GB (2 user and 2 for kernel) so that should not be an issue.

    CHeck the FAQ's on the MB and see if it might have a reporting quirk. I wandered around the ASUS site but they have made it very user unfriendly and I couldn't find anything excpet that Core 2 DUO might not boot unless you upgrae the bios.
     
    Last edited: Jan 25, 2007
  12. lancer

    lancer There is no answer! Political User Folding Team

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    i know this is my first asus board and i think their bios stinks in simple functionality, i much prefer gigabytes.....

    i looked at the dram settings, but they just dont make sense, neither does the manual help even though its 100 pages plus.

    i'll check each stick individually tomorrow and also run that program as well, hopefully i'll figure it out.
     
  13. NetRyder

    NetRyder Tech Junkie Folding Team

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    While this is true in theory (2^32 = 4,294,967,296 bytes = 4 GB), a 32-bit OS cannot map the entire 4 GB of physical memory to the address space in practice due to factors like memory-mapped I/O.

    Most modern devices on the PCI bus are also mapped to memory addresses in the 4 GB address space. Since these devices are 32-bit, they can only be mapped to addresses below 0xFFFFFFFF. So you have a portion of the 4 GB address space reserved for these devices, and the rest (3.2 GB in this case, but it varies) is the amount of physical memory that can be mapped to the address space. The rest of the physical memory is, in effect, non-addressable (unusable), even though it's available.

    With 64-bit, your total address space grows to 2^64 bits wide = 17,179,869,184 GB = 16 exabytes (!). So even though the 32-bit PCI devices get mapped to addresses below 0xFFFFFFFF (the 4GB boundary), any remaining physical memory can be mapped to higher addresses since the address space is so much larger.

    This is why you should be running a 64-bit OS if you have more than 3 GB of physical memory, and want to actually use all of it. :)
     
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  14. lancer

    lancer There is no answer! Political User Folding Team

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    would a 32bit program work on a 64bit os?

    i know dumb question, but it has to be asked.
     
  15. David_L6

    David_L6 OSNN Addict

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    NetRyder is correct.

    I have tried 4 X 1GB in a couple of different computers with both XP Home and XP Pro (32 bit) and all 4GB were never reported.
     
  16. NetRyder

    NetRyder Tech Junkie Folding Team

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    Yes, as long as it doesn't attempt to install 32-bit kernel-mode drivers or shell extensions. That's a tiny portion of software (mostly just defrag and antivirus tools, and the like), and most software vendors have already released x64-compatible versions of their products.

    The only real issue you might run into is hardware support, since not all hardware vendors release 64-bit drivers. This really depends on your system configuration - all my hardware worked with XP x64, and the Vista x64 RC builds.