yeah its heaka easy, make sure everything matches (except brands). try to match the latency and the timings also, cuz i had 512 on my notebook and i added another stick of 512 it actually slowed down my notebook. but when i actually matched the timings and the latencies it was much faster. notebooks seem to be a lot more picky about ram!!
MacBook 2.2GHz Santa Rosa | 120GB HDD | 4GB ram
Intel C2D E6300 @ 3.2GHz | 4GB ram | 880GB total HDD space | Gigabyte P965-DS3 | eVGA 8800GTS 640mb | Corsair HX 520 | Audigy 2 ZS platnium | Antec 900