Which OS is your Inspiron 3521. Maybe some driver is missing - download it from http://www.dell.com/support/home/us/en/19/product-support/product/inspiron-15-3521/drivers
You can install first Dell QuickSet Application and check for missing driver.
The World Is Not Enough
Original poster, If you have solved your problem, can you please mark the correct thread(s) with your solution. Thanks
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