Yes you can: You'll have to set up your raid array before you switch though. Build your raid array and install it. Windows has to have the raid card drivers installed before you can use it. That's why you set it up first. Then use a drive copy program like Ghost, or Drive image, and clone your Current hard drive to the raid drive. Then shut down the computer and remove your old C: Drive and reboot. You may have to tell the bios to boot from the raid drive. Windows should start up. If it doesn't then boot to the install cd and start setup and choose repair. Then you can reinsert your old hard drive back in and format it and use it as a secondary drive if you wish.