Some of your problem will be taken care of if you load the chipset driver.  After you have done that, the computer may be able to give you a better idea of what is missing.  The driver for the USB hub will be taken care of by the chipset driver, but if you have specific USB devices you will need to get a driver from the manufacturer of the device.  The PCI device is literally anything that is mounted on the main board to include the PCI expansion cards.

To find drivers for your machine on this web site, you need to move your mouse pointer to the top of this page, hover over your machine type (desktops, notebooks, etc) and select your model from the dropdown list.  The next page will have drivers and downloads in the first column, and documentation in the second column.  Follow the on screen directions to find the drivers and user's guide specific to your machine.

Good luck!

well, the problem is, i've downloaded a chipset driver, and i was told to download two more things [i was chatting with the dell support service people] and so i did what they told me, but those two things never went away...

so i was wondering if there'd be anything else to do?

Without knowing what computer you are using it is difficult to give specific advice.  The only general thing that comes to mind is that Dell issues Desktop System Software for some of their desktops that contain additional files for USB devices and certain optical drives.  You would find this in the drivers and downloads section; I think it is under the title of System and Configuration Utilities, but there may be another title.

oh, i have a Dimension E510 with Windows XP on it..