Win2k and second OS? dual boot

OK.. totally new system.. totally clean brand new HD preformatted and partitioned with Partition Magic 4

I purposely left the c drive empty for when I installed an OS on it after mounting it in my new box so prior to this 2k install it had some video files on the D and E drives but nothing ever went onto the C drive yet after installing 2k... when I boot it gives me the boot manager and there is an option for an "unknown operating system" as a second option. I haven't tried it to see what it does yet but there has been NO other OS install on this physical HD much less anything on that partition.

it used to be a slave to a 98 box and used for file storage but never at any time was ANY file put on the c drive.

it may be giveing you that because c: is empty so it assumes that ther eis a second os present

C isn't empty though.. I installed win2k on the c drive. I left that partition blank cause I didn't want ANYTHING on it before I installed the OS. So the C: partition was totally clean for the install. Which is why I am wondering where its finding this second unknown OS since its never had an OS installed on it prior to this first install. I doubt its partition magic since I have partitioned and formatted drives prior to the OS install, alot of times.

I noticed this the first time I booted up so I double checked.. nothing but standard 2k OS files (this was before I installeld ANYTHING)