|Some bioses have a setting in the bios Setup that can disable USB 2.0 support (it may not be called that). |
Go into the bios Setup and make sure all settings for USB are enabled.
If that / those are enabled....
XP must have at least SP1 updates loaded in it in order to support USB 2.0.
If it does.....
If the USB 2.0 support has a problem, that will show up in Device Manager.
(RIGHT click on My Computer - Properties - Hardware - Device Manager)
There will be one or more USB related Unknown or Enhanced devices that are flagged as not having drivers or as not working properly.
If there is a problem or problems there..
Apparently installing XP installs the main chipset drivers for your Intel 845G main chipset, but if they've been corrupted your USB 2.0 controllers won't be recognized.
You can load them again without having to un-install anything
Get them here:.
After the main chipset drivers have been installed and you have re-booted, look in Device Manager again - the problem USB related entries should be gone.
If they aren't, sometimes Windows leaves entries behind there that shouldn't be there - RIGHT click on each one, Un-install it, then reboot. Look in Device manager again - all should be well.
NOTE that sometimes front USB ports on a desktop case have inadequate wiring between them and the USB header on the mboard that can't support USB 2.0 requirements.
The ports built into the mboard on the back of the case, in the I/O area where most of if not all of the ports are, should support USB 2.0 devices just fine.
NOTE that you should have the Intel Application Accelerator listed in your All Programs list.
If you don't have that, your hard and optical drives are not running as fast as they are capable of.
In that case, go here, download the IAA, and install it: