Are you using an old monitor or did it come with the new computer? Contact Support if it was purchased with the computer after checking all the cable connections. Make sure to use the correct ports--the computer comes with integrated video but if you ordered a separate video card use that instead of the integrated ports.
We need more data...
* What specific monitor model?
* How is the monitor connected to the Inspiron 3662 using which port and cabling?
* What specific other monitor model did you test? Using which port and cabling?