I guess I will need help from the most skilled brains here!!
I am on W7 64B, with two 500Gbs WD blue (very sloow) on RAID 1.
The hard drives are conected to the SATA 3Gbs ports.
I am planning to buy two new Western Digital VelociRaptor WD4500HLHX 450GB
and have them connected to the SATA 6Gbs ports.
As far as I know I can break the RAID 1, replace the second hard drive, re-mount the RAID1, make a mirror from drive 1, boot from the new drive 2, and break raid and replace drive 1, mirror and remount Raid.
However, I believe that if I change the SATA ports in this process I will get problems right???
I know that interchanging them between SATA 3Gbs ports won't screw up the RAID but, I'm not sure about going to SATA 6Gbs ports. I wouldn't think it would be a problem. I don't think there is any harm in giving it a try. Otherwise you could always hook up one of the new drives and clone your raid over to it and then hook up the other drive to rebuild the mirror.
I had a bad experience a few months ago when I moved some long sata cables to distant drives on my case. At that time the computer won't boot because the mother board could not find the proper path and I had to find out where my drives were before.
I like your idea of installing the new drive on the SATA 6Gbs, mirroring the old C:, breaking Raid, installing the second new on the second STA 6Gbs and make the computer to boot from there.
I am not sure if there is any problems with files linked to C: that will never find the path again..??
Maybe reinstalling W7 fresh and reinstalling all softwares etc....will be less painfull.
I will post the solution here soon I get hands on it.