Hi! I have a Intel - DG41RQ (with an intel E2180 ). The MoBo has 2 RAM slots(DDR2). I previously had 1 1gig Memory running at 333Mhz and I'm thinking of buying another one at a different speed.
It is recommended to run ram with the same speed but most of the time ram with different speeds will run OK defaulting to the slower speed and it will not harm anything.