My monitor goes black every 30 seconds or so

Hello

I'm currently working on a friends computer and every thirty seconds or so the monitor will go black for 3 seconds and return to normal. Any Idea's as to what is doing this.

They have a GeForce FX 5200 for a video card and I've installed the latest drivers. Although I haven't rebooted the system after installing them. She tried installing the most currrent nvidia drivers and this issue still persisted.

Could this be another issue besides the Nvidia Drivers?

Thanks
Scott

The computer is only 2 - 3years old at the most it is a

Pentium 4 CPU 2.80 GHz.

She noticed the problem after she installed a program called Pinnacle Media Suite Home Video Editing.

Could this have changed some drivers somehow? If so is there a way to roll them back.

Thanks
Scott