So many words. The device manager can only solve part of the basic drivers problem. So when this built-in tool can help you, you can fix it by yourself. I know Dell provide the automatic install tool, so you can follow the Dell official tool to download and update it. Of course, you can download the driver by yourself.
For downloading drivers, the first choice the the brand computer website, because all the drivers such as graphic driver, audio driver are customized. If you cannot find it on the brand computer site, try to go hardware device official site such as NVIDIA, Realtek website. You can get more details from here: click here