mc2K, that is a good question.

The more volts you are putting onto your RAM, the less drive strength you need.
Don't know where but somewhere i read that the black slots were better for high performance RAM.

I assume high performance RAM will be more powerhungry so it is reasonable to say that high performance RAM is ran at higher voltages, therefore i assume it should have lower drive strength instead of higher.

This is just an assumption, don't quote me on it.