First of all, it us unlikely that upgrading your USB port will make your wireless go faster anyway as there are many other more likely things that can slow it down. In fact if it is reporting slow connection speeds, upgrading you USB will have no effect whatsoever.
You don't say what kind of PC you have however here are both answers neither of which actually answer your question but bear with me.
If you have a Laptop you should install a PCMCIA wireless card. It will work better than your existing USB one. (You can't upgrade laptops' USBs anyway.)
If you have a desktop or tower you should install a PCI Wireless card. Again it will work better than your existing USB one. You can buy PCI USB adapters but by the time you install one of those you could install a PCI Wireless Adapter for better efficiency on your PC.
t, November 2007
