6 Replies Latest reply: Feb 11, 2013 4:36 AM by trwarren239
trwarren239 Level 1 Level 1 (0 points)

My imac came with 8gb memory installed (4 x 2gb) and since memory is now cheap, I bought 16gb Patriot upgrade kit (2 x 8gb). I installed these into imac by removing 2 of the existing 2 gb and replacing with the 2 8gb (these were installed to lower 2 slots, lower meaning when imac was placed upside down to rest on display, these were the lower slots). The 2 new chips are the correct speed, etc. When I restart the machine, it shows only 8 gb of memory and in the system report is showing 4 x 2 gb chips. What does this mean??  I thought this should work, ie should now show 20 gb. The details from the memory page of the system report are shown below (unfortunately I didn't think to capture this data before the swap). Its as if lit thinks the old chips are still in even though they aren't; or is it somehow using only 2gb from each of the new chips? Its kind of cumbersome to take down the machine and try other combinations, but if I don't get any feedback, I'll try removing the other 2 2gb chips, leaving only the 2 new ones in. But, based on conflicting things I've seen on the internet, I'm not sure whether the new ones should be in lower or upper slots.

 

thanks for any feedback

Terry

 

memory page of system report AFTER swapping out old chips for new (its odd that they all show the same manufacturer as the old ones were original supplied by Apple, which are brand Hynix and new ones are Patriot:

 

Memory Slots:

 

  ECC:          Disabled

 

BANK 0/DIMM0:

 

  Size:          2 GB

  Type:          DDR3

  Speed:          1333 MHz

  Status:          OK

  Manufacturer:          0x80AD

  Part Number:          0x484D54313235533654465238432D48392020

  Serial Number:          0x0882ADA4

 

BANK 1/DIMM0:

 

  Size:          2 GB

  Type:          DDR3

  Speed:          1333 MHz

  Status:          OK

  Manufacturer:          0x80AD

  Part Number:          0x484D54313235533654465238432D48392020

  Serial Number:          0x0872ADA4

 

BANK 0/DIMM1:

 

  Size:          2 GB

  Type:          DDR3

  Speed:          1333 MHz

  Status:          OK

  Manufacturer:          0x80AD

  Part Number:          0x484D54333235533642465238432D48392020

  Serial Number:          0x584D1CAC

 

BANK 1/DIMM1:

 

  Size:          2 GB

  Type:          DDR3

  Speed:          1333 MHz

  Status:          OK

  Manufacturer:          0x80AD

  Part Number:          0x484D54333235533642465238432D48392020

  Serial Number:          0x585D1CAB


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