Yeah i know that i can have 3 gig ram in total just meant could i have like-

1 x elixir 512 ddr400 pc3200
and
2x corsair 512 ddr400 pc3200
(making 1.5 gig ram)
???

or

1x elixir 512 ddr400 pc3200
2x elixir 1gb ddr400 pc3200

or would it have to be-

3x elixir 512 ddr400 pc3200


Not sure if you can mix and match makes and gig sizes that what i mean?