No really, you should listen to yakwakdo, he has given good advice.
Nobody paid him to write such an extensive analisys of your problem.
Maybe you did a lot of thoughtful investigation of your problem but reading this thread gives the impression like you've randomly tried things without following a logical path.
Take for instance when you start blaming ATI (AMD) for releasing buggy software, maybe it is so but your problem has nothing to do with their drivers.
Remember you've problems installing XP.
1. Bad cdrom media
2. Bad optical drive
3. Bad cable of optical drive or hard disk
4. Bad memory... and so on.
Or you could believe the trendmicro support. They're paid to give you an answer, most of the time not the correct one but the one will get you off the phone as soon as possible.
Not blaming trendmicro specifically, most support desks are like this. Quantity over quality.