Reformat Drive w/QNX Realtime Installed

I bought an older used PC (Pentium 200 MMX) that has QNX Realtime installed in it. I know nothing about it and wish to reformat the drive to install Windows 98 on it. By using a Win98 startup disk, I was able to get to the a: prompt, but I cannot get to a c: prompt to do an FDISK. How should I proceed from here?