USB disconnect in XP

After I installed XP pro, all my USB/ PS ports are disconnecting after some time. I have tried to adjust the USB properties (powersettings) where applicable, but it did’nt work.
I have cordless Logitech keyboard/ mouse, HP PSC750, cardreader, etc.connected to USB.
For the printer I have intalled at hotfix from HP, but that did’nt work either.

Can anyone please help?