Q: Macbook running slow - only 12MB of RAM leftover.  Should I install more DDR?

How much RAM is installed?

Memory limitations: Using Activity Monitor to read System Memory and determine how much RAM is being used

Installing more memory is a simple do it yourself project. Apple even provides the instructions.

Yes, install more

Allan

Crucial.com or macsales.com

Which ever one is cheaper this week

Allan

More would be better.

There are only two recommended RAM vendors these days, Crucial and OWC. People have reported problems with many other brands, yet Crucial and OWC's prices are as good as any you are likely to find.

Go to Crucial and download the little app that examines your system and recommends RAM upgrade options.

Their prices are good but don't have to buy memory from them - determine what you need and buy it from Crucial or OWC / MacSales.

Apple's installation instructions: http://support.apple.com/kb/HT1651

OWC has even better instructions including a video.

Make absolutely certain of your MacBook's model. There are many 13" MacBooks with maximum memory configurations of 2, 3, 6, or 8 GB.

Click the "How to find your model ID" on this page:

http://eshop.macsales.com/shop/memory/Apple_MacBook_MacBook_Pro/Upgrade/Macbook_ selector

The model 1,1 (Early 2006) can use 2gb of 200 pin 667mhz PC2-5300 RAM
The model 2,1 (Late 2006 & Mid 2007) can use 3gb of 200 pin 667mhz PC2-5300 RAM
The model 3,1 (Late 2007) can use 6gb of 200 pin 667mhz PC2-5300 RAM
The model 4,1 (Early 2008) can use 6gb of 200 pin 667mhz PC2-5300 RAM
The model 5,1 (Late 2008, Aluminum Unibody) can use 8gb of 204 pin 1066mhz PC3-8500 RAM
The model 5,2 (Early 2009, 2.0GHz Model Only) can use 6gb of 200 pin 667mhz PC2-5300 RAM
The model 5,2 (Mid 2009, 2.13GHz Model Only) can use 6gb of 200 pin 800mhz PC2-6400 RAM
The model 6,1 (Late 2009, White Unibody) can use 8gb of 204 pin 1066mhz PC3-8500 RAM
The model 7,1 (Mid 2010, White Unibody) can use 8gb of 204 pin 1066mhz PC3-8500 RAM