Ram Config for Mac Pro

[davewolfs]

Hey folks,

I am looking to upgrade a mac pro from 2GB to 8GB. I am curious to know if mixing and matching memory has a serious impact on performance. Should I buy 6GB as 3x2GB chips and use the existing 2GB of memory, or am I better off buying like 8 1GB sticks. I am sure many of you have gone this down this upgrade path, what type of memory configuration are you using?

[Jonathanoee]

You will get a faster memory if you fill all the slots. So 8x1GB is best.

Here a test that confirms that
http://www.barefeats.com/harper3.html

[surflordca]

Faster yes but nothing you will notice. I bought 4 x 2GB and use the 2 that came with it for a total of 10 GB.

[thetoness]

Faster yes but nothing you will notice. I bought 4 x 2GB and use the 2 that came with it for a total of 10 GB.

I want to do the same thing. How did you configure your ram? Specifically, where did you place the two 1gb ram sticks? Thanks.

[Volante]

Can you install 3x2 extra anyway, don't they need to be in pairs?

[bigbird]

Should I buy 6GB as 3x2GB chips and use the existing 2GB of memory, or am I better off buying like 8 1GB sticks.
I wouldn't recommend either method. Memory MUST be installed in pairs, otherwise it isn't recognized. I'd get 4 X 2GB, and place them in risers A & B, slots 1 & 2. Then put your Apple RAM in riser A, slots 3 & 4. Buying 8 X 1GB fills all eight slots, meaning if you need more RAM later, you'll have to get rid of some of the 1GB sticks.

[Jonny427]

To quote barefeats:

A better scenario, if you insist on using those two factory 1GB FB-DIMMs is to order four 2GB FB-DIMMs, pull out the two factory 1GB FB-DIMMs, put the four 2GB FB-DIMMS in slots 1 and 2 on each riser, and put the two 1GB FB-DIMMs in slot 3 & 4 of the top riser. That will give you a total of 10GB.

[bigbird]

Johnny, did you read the thread immediately above before you posted?

[benpatient]

considering how close together your post and his are, i'd say it's safe to say that he didn't read your post, because it wasn't there when he was reading the thread.

[DeuceDeuce]

I bought two 2gb chips and have two 1gb chips, how should I structure them.

Do I keep the 2 2gb chips together in the bottom riser and have the two 1gb chips together in the top riser?



EDIT:

Never mind, found the answer at OWC.

[rpaloalto]

I would do this

1. 2 gig top slot 1
1. 2 gig bottom slot 1
1. 1 gig top slot 2
1. 1 gig bottom slot 2