OK thanks. I don't think the card I linked to was 2.0 though, I think it's just regular PCI-E x1.
So if you have say 6 slots on the mobo vs. 6 slots on the controller card, then an array with 6 drives would be faster if it was connected via the mobo instead of the controller card? But, the difference would probably not be big?
What about PCI (regular, not express) - what is the bandwidth of a regular PCI slot, and which controller card would be faster - a PCI one or a PCI-Express x1 one?