failing USB problems!

Hi all
This is my first post and im sorry that it has to be a Q not an answer
but i wud gr8tly appreciate u guys help

i have recently purchaseda second hand IBM thinkpad T22 laptop

i have now realised that the usb port on the machine does not work as i expected it to, when i a large amount of applications etcare open - the port seems to "restart" itself - the adsl modem restarts and everything that is plugged into the hub attatched to the modem also acts as if its just been plugged in - i have all the new drivers for the laptop as far as i believe but the problem remains - i was advised that xp sp2 contains advanced usb support however after installing that i still have the problem. it happens both when it is running on both ac power and on battery. if possible - i would be extremely greatful for your responses, as i have just spent what,to me, is a large amount of money on the machine and i would be very dissappointed to fin out that it may in fact be faulty:(

Thanks guys

Samputer