Upgrading Memory

As long as the RAM is compatible with your machine and you're happy with the reviews it will work. The speed difference between 1333 and 1066 shouldn't be something you'd notice without running a benchmark to see the difference. As long as the 1333 is something like 1066/1333/1600 compatible and your Mac can handle it then I would go for the cheaper and faster RAM if the reviews on it are also good.

Remember though that cheaper and faster doesn't always mean better. It could be made in poor fashion or the timings (another thing to look at past clock speed) and whether it's dual/triple channel will add into the performance factors.

You may also want to check other websites with detailed information about RAM like overclock.net

Because of the internal bus speed, your RAM caps out at 1066 MHz. You won't any speed benefit from the faster RAM. You might not have any problems running 1333 MHz RAM, but then, you might. 1066 MHz RAM will work. OWC is great, Crucial is excellent as well.

DO NOT repeat DO NOT go with the 1333 RAM, it will probably cause problems including Kernel Panics. If you are going to upgrade the RAM purchase the RAM that is specified for your computer!

You can purchase high quality correctly spec'd RAM from a number of sources including OWC (www.macsales.com) and Crucial, NewEgg etc...

evolon8, before you make your RAM purchase, be sure to read the terms and conditions of how the RAM is warranted. At least one company has the following clause in its limited lifetime warranty:

+“Company X”, at its option, will repair, replace, or provide a credit or refund of either the original purchase price or fair market value, whichever is lower, of any product that is determined by “Company X” to be defective.+

If I were in the market for RAM with a limited lifetime warranty, I would consider the possibility of a refund of future fair market value, rather than replacement of the defective RAM — +at the warrantor’s option+ — as being too limited. However, if you’re not planning on owning your MacBook Pro for several years, then that might be a moot point for you.

In any case, be sure to follow the advice of neuroanatomist and rkaufmann87 — wherever you choose to buy your RAM, be sure that it meets the specifications of your MacBook Pro. If the RAM doesn’t meet those specifications, and it somehow damages your MacBook Pro, then that damage would not be covered by Apple’s limited warranty!