Vista - Computer boots only after several trys.

This is my first post to this forum. I have Vista Home Premium.

When I turn my computer on, it sounds like it's booting but it's not appearing on the moniter.

That said, it takes from 2 to 5 attempts powering off and on to boot. Sometimes I get the analog/digital icon at the upper left of screen. Sometimes it's steady, sometimes it flashes. Sometimes the words (BIO's?) start to appear then disappear to black screen. Sometimes the screen flashes the BIO's, then black screen. It's always different. Then it will start to boot. I get the screen "Start Windows Normally". Then it boots.

I've installed nothing. Only automatic updates. I did a virus scan and a spybot S&D which showed nothing.

Any ideas? Thanks for any help.
Norma

Hello Nls,

Welcome to the Forum.

Did you try to repair boot manager using the Vista installation disc. If you don't have Vista disc please follow these two tutorials How to create recovery disc and how to perform startup repair. If this repair won't help, try to perform the repair installation of Vista. To do this repair you will have to get the original installation disc.

Hope it helps. Cheers...