USB root hubs

Hi,

I am looking out for an answer from quite a long time. I posted it on wiki-answers too. But didn’t get a reply so far from anybody. Hope I could get some responses here in this forum. The question is: “How many USB root hub entries would I find in Device manager (Win XP) if I have 4 USB ports on the PC”. Given ‘n’ USB ports what would be the number of entries in Device Manager. I ask this because – the number of USB root hub entries are different from the number of USB ports on the computer.

Awaiting responses.

Thanks !!