I know this is a very old post, but since Google lists the question close to the top, I thought I'd add the answer to it.
The way to get an Intel D975XBX Motherboard to recognize individual drives (not in a Raid set) on the Blue Silicon Image SATA 3114 headers is to remove any drivers you installed, delete or rename any associated Sil 3114 INF files in the windows/inf directory and reboot.
You can find the INF files by using search,[word or phrase in the file] and look for "Si3114"
It will be in an OEMxx.inf file.
When Windows detects the Raid controller, just hit cancel and do not install any drivers.
If will complain about the device not being installed correctly, but the four ports will all revert to non-raid and any devices you have connected will function normally.
If you want to use it as Raid again later, simply re-install the Raid drivers from Intel's web site.