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gmd1129

macrumors newbie
Original poster
Jul 24, 2011
11
0
I have a mid 2010 13 inch Macbook Pro and decided to upgrade the RAM from 4GB to 8GB. I ordered the Corsair 8GB (2x4GB) PC3-10666 DDR3-1333 SO-DIMM 204-Pin Dual Channel Notebook Memory Kit but when I installed the new RAM, Lion would not booth, it would freeze during the booting stage. I was thinking that it may possibly be bad RAM but I was wondering if there are any thoughts/suggestions before I go contacting the seller. Any input? Thank you in advance.
 
Make sure the RAM is seated properly. That is usually the problem. If you push it in very firmly and it still won't boot, put your old RAM in and see if that works. If it does, then I'd contact the manufacturer.
 
Thank you for your help. The RAM is placed in firmly but I just tested the RAM and something strange occurred. I tested each 4GB stick with a stock 2GB stick and both of the 4GB sticks work fine when paired with a 2GB, yet when the 4GB sticks are put together, they do not work. Very strange.
 
No, it recognizes the 6GB. It's very strange.

What? When you go to About This Mac > More Info > Memory, does it show them both? You should be able to handle up to 8GB, but I'm not sure if it can handle 1333 MHz RAM. If you put in the 2GB stick, Lion can run off of that, but if your machine cannot handle 1333 MHz, it will not use that. This would explain your situation.
 
It shows the 4GB stick but downgrades it to 1067 MHz. So I can't have two 1333 MHz RAM sticks ? I figured the computer would downgrade both to 1067 MHz but I'm guessing I was wrong.
 
RAM typically contains a number of performance profiles stored in an EEPROM on the DIMM itself, allowing the stick to be "backwards compatible" so to speak. In a perfect world this would always allow memory to function in a computer, alas, that is not the case.

Your computer may decide upon finding higher performance profiles than it supports, to not like the memory and then wonk out. Or it is simply incompatible with your system. DDR3 RAM is meant to be standardized, but in practice one stick may not work in one system but will in another.

Often manufactuers of PC motherboards have lists of certified memory that has been tested and verified to work with each product which you can look up on their website; I don't know how Apple does this however.

Usually the best idea is to use only identical modules, and not mix RAM of different models, sizes, speeds, timings or from different manufacturers.

If you have access to another laptop you could try the RAM in that one, see if it works. Otherwise you may want to contact your place of purchase.
 
It shows the 4GB stick but downgrades it to 1067 MHz. So I can't have two 1333 MHz RAM sticks ? I figured the computer would downgrade both to 1067 MHz but I'm guessing I was wrong.

It may be showing 1067 MHz because that is the highest it can support. it may not even be using it. You should see if you can get a refund and go for 1066MHz sticks instead.
 
Sorry you're having issues, but I'm really not surprised because you're using slightly the wrong parts. If your Mac came with PC3-8500 then just use that. We can all sit here and guess why the board can't downclock both sticks, but at the end of the day you still can't boot with 8GB.

If you can, I'd send it back and try to exchange it for the proper part. Also, given what I've read about DOA sticks and MBPs just plain not liking corsair RAM, I'd get a different brand as well. Newegg reviews are not good for the corsair 8GB kit (3 eggs is terrible for RAM - like 4/10 are DOA/No boot).
 
Hi.

I'm having a problem related to this.
I bought 2*4GB PC3-8500 1066MHz RAM modules, but my laptop won't accept both modules.
I've tried every combination with the 2GB & 4GB modules, it works with 6GB but not with 8GB.
When I boot I've only got a black screen.

Any suggestions to how I can fix this problem?
 
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