Best type of memory for X61?

[alosito]

Crucial.com shows that X61 can both DDR2 PC2-6400 and DDR2 PC2-5300 with a maximum of 2GB per slot. I am thinking of upgrading my X61 with 4GB og RAM. Would would be a better option to get PC2-6400 or PC2-5300?

[Comage]

Get the one that matches your FSB speed.

[erik]

800 MHz modules will downclock to 667 MHz so get whichever is cheaper.   speed will be identical between the two.