ld13
Honorary Master
DDR3 on LGA 775 isn't abnormal at all, all of the later boards were DDR3. In fact, I don't know of any P43/P45/X48 boards offhand that used DDR2.
I've had a few go through my hands.
@OP, what RAM are you trying to use?
RAM: Patriot PSD34G133381.
CPU: Q6600, E6600 and Q9300.