Excerpt: Used 2 of these 2 4GB SO-DIMMs to upgrade MacBook Pros (Early 2008, models 4,1 & 3,1) up to 5GB & 4GB ram respectively. Memory seems to work very nicely. For abt $ it was possible to significantly upgrade 2 laptops! Can't achieve nearly the same thing with MB Air which is hard-soldered at 1GB.
Swapping out the old 2GB stick for this was quick and easy - I put it into the first slot by ...
13 April 2015
Summary: Bought this to upgrade my Early 2008 15" MBP which already had 4Gb or RAM but was throwing the spinning pinwheel all too often. Swapping out the old 2GB stick for this was quick and easy - I put it into the first slot by removing both sticks and putting it in first - and it's like having a whole new...
Summary: Upgraded old MAC ram, wish it would come down in price, but product worked well. Old 2gig stick it replaced only sold for $13 on ebay, so this stick is worth its weight in gold. Saved my MAC from a OS upgrade/Paperweight issue.
Summary: I installed a 4GB and another 2GB Crucial memory in my Mac Mini (Late 2009) after reading blogs around installing memory beyond Apple supported memory of 2GB to find out that the performance increased amazingly. The response time is now as used to be when I bought the computer back in 2009.
Summary: Bought it for a 20", mid 2007 iMac which had 4GB of RAM and was prone to spinning beach balls. Replacing one of the 2GB sticks with a Crucial 4GB increased my Mac's memory by 50% and made it usable again. My only complaint is that I wish I had known the iMac's real memory limit earlier.
Summary: Used this to upgrade an older Macbook Pro past the officially supported 4GB. Already had Crucial sticks in the laptop, and have used Crucial in other computers in the past, so, knew this would be quality memory.
Summary: worked well on my MBP 2.2GHZ, 2008 - I wanted to upgrade to the max, 6GB - even though Apple lists this model at 4GB. It runs smooth and haven't had any glitches. Running this 4GB from Crucial an 2GB from someone else with no issues. Main use is for Music production and day to day use.
Summary: Works like a champ in my late-2008 MacBook Pro. The specs say that that model only supports 4GB of memory, but I put this module in along with one of the existing 2GB modules, and it now uses all 6GB. A great way to give a little more life to an old machine!