|"I had to reinstall the OS (XP) because of a unconquerable virus (Mcaffee never saw it coming)."|
Most malware these days is not a virus.
If you had come here and detailed your symptoms we might have been able to help you get rid of it without you having to re-install XP.
E.g. there is a lot of crap being installed by the makers of "rogue" anti-malware programs - you often get it merely by visiting contaminated web sites, often when you search for something and click on a "hit". The symptoms make it appear your computer is severly infected, but they're FAKED - no actual harm has been done. The intention is for you to buy their anti-malware program - their software scans for free but doesn't remove anything till you pay for the program. The makers of "rogue" anti-malware programs change what and how the crap is installed often enough that most legitimate anti-malware makers can't keep up and they detect nothing wrong, or they do detect it but can't get rid of all it's symptoms. There are a handful of anti-malware makers that specialize in getting rid of thecrap - Malwarebytes probably being the best one.
Whenever you load Windows from a regular Windows CD (or DVD) from scratch, after Setup is finished you must load the drivers for the mboard, particularly the main chipset drivers, in order for Windows to have the proper drivers for and information about your mboard hardware, including it's AGP or PCI-E, ACPI, USB 2.0 if it has it, and hard drive controller support. If you have a generic system and have the CD that came with the mboard, all the necessary drivers are on it. If you load drivers from the web, brand name system builders and mboard makers often DO NOT have the main chipset drivers listed in the downloads for your model - in that case you must go to the maker of the main chipset's web site, get the drivers, and load them.
E.g. the USB 2.0 support for your mboard is NOT installed in Windows until AFTER you install the main chipset drivers.
USB devices may not work correctly when they're connected to certain USB ports, e.g. ports in a hub or on the front of a desktop case.
See response 3 in this: