I am about to build a PC.
I have ordered the following components:
motherboard: ABIT KN9 Ultra
CPU : AMD AthlonX2 4200+
memory : CRUCIAL 2Go (2x1Go), DDR2-667
GPU : ASUSTEK NVIDIA 7600GT 256MB (fanless cooling)
hard drive : Seagate 320 Go SATA2

Considering the ABIT KN9 Ultra supports DDR2-800, should I expect compatibility problems with DDR2-667 or a big performance drop (compared to a config with DDR2-800 like the one tested in the Abit KN9 Ultra Phoronix article)? Should I try to modify the order and get DDR2-800 DIMMs?

This config will only run Linux. I don't play games much, but I would like to have Flightgear and X-plane run smoothly with all the optional eyecandy.