keyboard and mouse problem with X11

[Alessio Ciregia]

Ok, fedora is up to date.
My PC is dual PIII processor (itry MPS 1.1 and 1.4).
My PC video card is dual head (radeon 7000).
In the runlevel 3, all goes well, but when I use gnome...
...the keyboard seems to write more characters than I press!! Also for 
the mouse, it clicks more times than I do.
This is not a sporadic event, but it is random.

??

bye