Glad it worked.
No genius here. If you do this for a number of years, it becomes routine.
You can look the code up on the net (bing or google). There are a number of databases which will identify to what device the code belongs. Once you know the device (card), then just go to the manufacturer site. Or, if it is an NVidia or AMD chipset on the card, just go to NVidia or AMD, regardless of the manufacturer. Sometimes, Windows Update will detect the proper driver and provide it. If Windows Update does this, it is because the manufacturer has provided the driver to Microsoft. If there is no driver, Windows will use a generic driver if possible (which is what you had).
The drivers that you tried from the Dell site were specific to the graphics chipset on the motherboard. The card you installed, while having an AMD chipset, was a different chipset, and thus required a different driver.
Now, the good news is that you did not use one of the several thousand garbage driver download sites on the web. These are a hoax, and are often there to play you for a fool, or their download can carry an unwanted payload. If the manufacturer of a device does not have the driver on their webpage, there is no point in using one of those garbage sites. I actually have another name for them, but we are on a public forum. In short, I always go to the manufacturer, as that is the safest place to get the driver.
No, I am not a full-time tech. I only help where I can. Intel puts up with me on their forum.<G>
Again, glad all is working.
Cheers,
Doc