Re: DRIVER NEEDED: Dell Computer GX270 (Windows XP Professional) [USB]
Support for the USB Controller comes from the OS and from installing SP1, SP2, or SP3. Without the service pack installed, you will only get USB 1.1 support. With the SP installed, you will get USB 2.0 support (only if your controller is a USB 2.0 compliant controller). Some older machines only have USB 1.1 controllers.
Drivers are installed automatically without user intervention anytime the system "sees" a usb controller is present and enabled. In the case on on-board controllers, there may be a bios setting that can disable the usb controller.... just make sure it's enabled (in BIOS) if you have that type.