MacBook Air not detecting Dell monitor with DVI-D to Thunderbolt cable

Cannot detect Dell E2311H 1920x1080 monitor when it's connected via DVI-D to Thunderbolt cable on my OS X Yosemite 10.10.5 MacBook Air . (Works fine with VGA to Thunderbolt cable). Both were powered down when I connected the cable. Dell is set to use the DVI-D port. Nothing shows in MacBook Air Display screen, when I select 'Detect Displays'. Tried holding down <option> and choosing 'Scaled', but none of the options match 1920x1080 resolution on the Dell. Tried a few with no success.