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I have an early 2009 Mac pro (2.66 Quad-core) if I get 12GB DDR3-1333 (http://www.crucial.com/uk/store/partspecs.aspx?IMODULE=CT3KIT51272BD1339) will it work ok/clock down?

Are there any negatives in getting it over the recommended DDR3-1066?

I thought if I get the 1333 I'll be somewhat future proof (in case I get a new Mac Pro in the next year or two).

Any thoughts on this? thanks!

No cons. It'll just perform as 1066 mhz, and you'll be able to use the kit with newer hardware.
 
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