Computer screen just goes blank

[Hetz Kyle]

I have had my computer for about 1 1/2 yrs. and have not
had any problems until just recent. We can be on the net
and be going to a site from a browzer and the screen goes
blank and then acts like it is going to reboot, but
doesn't. The monitor power light will flash like the CPU
is off. The only way to get the computer going again is
to shut down and reboot. This same thing has happened
while the computer is on, but isn't being used. The only
thing I have tried is system restore. Do you have any
suggestions? Thanks