They are good PC speakers. they run for about 200 as they said.
If you are more into music, i would suggest a decent receiver and 2 floor standing speakers capable of good base.
If you are a "gamer" the 5500 will be nice. They also have a optical s/pdif for digital sound. This will not produce 5 channel sound though, unless the sound track is encoded in dolby try digital surround sound.
My current specs:
Biostar TPower x58
XFI GTX260 Black Edition
640 WD Caviar Black
Vista Home Premium x64