Make sure the Dell chipset has ben installed. The chipset allows the operating system to find and use devices integrated into the mother board. Enter your service tag here then download / install the chipset
https://www.dell.com/support/home/en-us?app=products
--please don't forget to Accept as answer if the reply is helpful--
Regards, Dave Patrick ....
Microsoft Certified Professional
Microsoft MVP [Windows Server] Datacenter Management
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