Are onboard raid controllers based on Intel ICH10R southbridge still considered software Raid?

Solution 1:

Yes, it's software RAID. To get hardware RAID you need a RAID card, and the cheaper ones aren't even hardware RAID. A good hardware RAID card will almost always outperform a software solution, but with your CPU you shouldn't notice the difference.

You're better off using the Windows RAID tools for Dynamic Disks. The only advantage to using the onboard RAID (which is still software RAID) is that you can RAID a boot volume, but there are a ton of drawbacks.

Solution 2:

Mark is right on the money. A dedicated card is best if you want to include your boot drive and OS files in the RAID array. But it really depends what you are doing, because using software RAID in Windows management will suffice for most things.

And as of Windows 7 Ultimate I know for a fact that it does support RAID 5. Not sure about Vista or XP.