Does ram NEED to be installed in pairs

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Does ram NEED to be installed in pairs

Hey guys, just purchased my Mac Pro about a week ago and I was looking to upgrade my ram. I ordered a 2 gig stick and it arrived yesterday but it won't install. I remember reading ram needed to be installed in pairs but I wasn't sure how true that was. Can anyone shed some light on this?

Thanks

2.66 Quad Core Mac Pro, Mac OS X (10.4.7)

Posted on Sep 15, 2007 6:01 AM

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Answer 1

Sep 15, 2007 6:13 AM in response to Matrixfan101

YES. It needs to be installed in pairs and it really should be pairs from the same manufacturer.

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Answer 2

Matrixfan101 Author

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Sep 15, 2007 6:15 AM in response to Matrixfan101

So without having a pair of ram, it won't work at all? Also, anyone know of any good places to buy cheap ram. Looking to spend about 150 for 2x1 gig sticks.

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Answer 3

Sep 15, 2007 9:50 AM in response to Matrixfan101

DIMM's MUST be installed in pairs as the memory controller interleaves between DIMM's to match the FSB speed.

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Answer 4

The hatter

Level 9

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Sep 15, 2007 10:39 AM in response to Matrixfan101

http://docs.info.apple.com/article.html?artnum=304492
http://www.apple.com/macpro/expansion.html
http://manuals.info.apple.com/en/MacProMemoryDIMMDIY.pdf

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Answer 5

Sep 15, 2007 10:50 AM in response to Matrixfan101

Be aware that you additionally probably bought the wrong model RAM. RAM that is specifically rated for use in the Mac Pro is rarely, if ever, sold singly. As they must always be installed in pairs you will hence always buy a kit that comes with a pair of FB-DIMMs.

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Answer 6

Sep 15, 2007 11:12 PM in response to Matrixfan101

eBay is your friend if you're looking on the cheap side...

You could look for Nanya or Micron DIMM that are OEM on Apple. Often people will resell their old ram to make place for some bigger DIMM.

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