best memory for T400 P8400

[T400plus]

My T400 has 2 GB(1+1) which Lenove bundled with the box. My next project which does extensive in memory manipulations
will work much better if I have 4-8 Gb of free memory.
What would be a good time to upgrade and with what type of memry.

[Marin85]

I would recommend you reading

http://forum.thinkpads.com/viewtopic.php?f=45&t=73702

Cheers

Marin

[basketb]

My T400 has 2 GB(1+1) which Lenove bundled with the box. My next project which does extensive in memory manipulations
will work much better if I have 4-8 Gb of free memory.
What would be a good time to upgrade and with what type of memry.

Didn't know Sudoku was that memory hungry . (though in three dimensions it is very CPU intensive).