SATA Ports with add-on card and speed

Hey guys, I have trolled here for years and now have a specific question that I would like an opinion on:

My MB is an abitIP35 PRo. This MB's SATA ports are 3gb/s. Over the years I have upgraded and most of my drives now are 6gb/s. If I install a PCIe card with 6gb/s ports will this actually be faster than just using the 3gb/s ports on the MB?

I ask because many reviews of different PCI cards have comments regarding the speed of the card ports not even being as fast as the slower 3gb/s ports on the MB. Any info would be great, thanks!

Are you using hard disks? If so, then it won't help because they can't saturate a 3 Gb/s port.

Hard disks have a transfer rate way below 3 Gb/s. View the benchmarks of a VelociRaptor (which probably is faster than your hard disks): http://www.maximumpc.com/article/n [...] enchmarked

SATA 6Gb/s controllers have their uses. They are required to to give modern day SSDs the required bandwidth (which is quickly running out!). But slapping a 6Gb/s compatible sticker on a mechanical drive is nothing short of a misleading guise designed for no other reason than to extract more money from unknowing consumers.

Same performance, but it's easier to sell a 6Gb/s drive.