Not all my RAM is showing up...

Discussion in 'Mac Pro' started by rockinrocker, Jan 15, 2009.

  1. macrumors 65816

    rockinrocker

    Joined:
    Aug 21, 2006
    #1
    So I have the stock 2X1 and 4X2 aftermarket.
    None of the sticks that I put in the second riser will show up.


    I tried the 2's in A1,A2,B1,B2 then the 1's in A3,A4.

    I then tried the 4 2's in riser A and the 1's in riser B.

    It didn't seem to matter, all that would show up is what was in Riser A.

    Could it be a bad riser or something?

    [​IMG]

    [​IMG]
     
  2. macrumors newbie

    Joined:
    Jul 25, 2002
    #2
    I would first try reseating the riser first. If that doesn't work I would try swapping them find out if it's the riser or slot on the mobo. Last I would try swapping only a couple of the new dimm's to make sure one isn't bad and throwing the whole riser off. Not sure if that would happen though.
     
  3. macrumors 6502a

    Rt&Dzine

    Joined:
    Oct 8, 2008
    Location:
    12 across
    #3
    Bad riser is possible but have you run Apple Hardware Test? Did you try it with only the stock 2x1 RAM (one on each riser).
     
  4. thread starter macrumors 65816

    rockinrocker

    Joined:
    Aug 21, 2006
    #4
    Both risers have been in & out several times.

    I thought default position was A1 & A2?
     
  5. macrumors regular

    Joined:
    Feb 17, 2008
    #5
    Any red lights on the riser? red lights mean a bad chip or bad riser.
     
  6. thread starter macrumors 65816

    rockinrocker

    Joined:
    Aug 21, 2006
    #6
    Ah, there is indeed a red light on on riser B. It's there regardless of which modules are in it.
    Diagnosis: bad riser?
     
  7. macrumors 6502a

    Rt&Dzine

    Joined:
    Oct 8, 2008
    Location:
    12 across
    #7
    No. If you have a 2008 Mac Pro, the performance will suffer if you have RAM on only 1 riser.
     
  8. thread starter macrumors 65816

    rockinrocker

    Joined:
    Aug 21, 2006
    #8
    OK, so I put the stock sticks (stock sticks?) only in, A1 and B1, and they both show up fine.

    I put all 6 sticks in (A1-4 B1&2) and neither of the B riser sticks show up.
    Closer inspection reveals there's a bright red light on on the riser next to the DIMM 2 label on the riser.

    If the second slot on Riser B was bad, would that cause both sticks in that riser not to show up?
     
  9. thread starter macrumors 65816

    rockinrocker

    Joined:
    Aug 21, 2006
    #9
    yeah, hardware test confirms it.

    note to self: in the future, just run the stupid hardware test first.
     
  10. macrumors 6502a

    Rt&Dzine

    Joined:
    Oct 8, 2008
    Location:
    12 across
    #10

Share This Page