Thanks for your imput! But I am computer dumb. How do I run in Bios? Also how do I connect to external screen?

If it is hardware like I think it is wouldn't it show up in diagonostics?

Sounds like a hardware issue to me.  You could always try another harddrive in your pc or yours in another.

 

Or leave the system in the BIOS for a while.  Generally the BIOS runs the system at about 70% cpu power, so it does make it work harder than you'd think.  If you can get the screen to go wonky in there you've proved it's not a software issue.

Also, you could try connecting up an external monitor, if it's software it should show on both monitors, if it's hardware should only show up on the lcd display.

Send it back while you can.

Call Dell asap for help with a new computer. Don't try anything yourself. Dell will instruct you how to return for a replacement if necessary.

have you checked t make sure the cooling fan inlet isn't blocked off, or plugged with dust...if it is the CPU will overheat and freeze it and do all sorts of weird things. if it is taking a matter of minutes to happen it sounds like a heat buildup problem to me. (the very same thing happened to me on my inspiron 5100 once when i left it running on a soft cushioned chair while i was answering a telephone call, just locked up solid and i could feel the heat (very hot by the way) coming out of the exhaust port in the back.

Dell won't do anything they say it is a software problem.

Its quite unlikely that its a software problem.