Contact dell if there driver isn't working.
The only next thing for you to do is use the dell recovery partition to reinstall your OS to working condition. Since driver sweeper sometimes removes a little more then its suppose to.
Nothing you can really do except what you've already done.
I5 3570K@4~5.0ghz: Gigabyte GA-Z77X-UD3H:Corsair Hydro H110 :16GB Corsair Vengeance DDR-3 1600: XFX Radeon 7950 @ 1100/1575 : Corsair AX 860 PSU: x2 WD Black 1TB HDD's: 90GB Agility 3:Creative Labs X-FI:Corsair 500R Arctic White Edition:3 22inch Monitors Eyefinity @ 5294x 1050 : Alienware Tact-X Keyboard: Razer Naga :Corsair Vengence 1500 Headset: Corsair SP2500 Speakers