Wakey

I bought a new computer with Vista home premium installed. I have not
installed much yet because I have been having problems 'restarting'
and'shutting down'. In essence when i shut down or restart the computer it
closes down to a certain point where the computer is still on but with no
functionality i.e. no image being sent and no computer noise from the
hardware working. At this point I have left it for over 30 minutes and in
the end had to shut it down by pressing and holding the power button on the
fron tof the computer. To restart I have to turn the power off at the back
of the computer as if i don't all I get is the whirling sound of the fan at
initial start-up continuously.

Any idea???
--
msw