I have a DELL Inspiron 530 and it has 4 Ram Slots - in pairs, one with black tags and the other with grey. I have one GB installed at present in the grey slots. Would the black slots be for another kind of RAM? How do I know which is SDRAM slots and which DDR slots?
As I just did this exact same upgrade, I feel confident my answer is right; You will need two RAM-units (ex. 2x1 gb ) to upgrade it, this meaning; you will need to follow the color-coding (grey/black) as you insinuated.
Hope this solves your prob- Did for me, and a major performance change is a fact :)