I don't know about Powerquest, I don't use it, I use acronis when needed.
For these sort of tasks I use XP's built in software. If you do use XP you could right click my computer > pick manage > then disk management. The drive with the unallocated partition should show in the right hand window. Right click on the unallocated space, you will get a drop down menu. Format or create partition should be listed.
this should do the job for you.