How can I change where my files are backed up to when changing to iOS 5?

Hi,

I have a Windows PC with two hard drives, one being an SSD and another being a regular hard drive. I use the regular hard drive to store music, movies, media, all of that good stuff; I use the SSD to store the operating system and a few video games in order for better performance. My question is, why, when I try to change my iPod to iOS 5, does it automatically back up to my SSD (C:) drive? Is there any way that I can change the location to which my files are backed up? I have plenty of space on my second hard drive, but I can't find anywhere in iTunes where there is an option to change this.

Thanks!