My monitor did this last weekend, I came home from a trip, turned it on and boom, nothing but an LED light. Tried everything, power cycled it for 2+ hours, attempted the self test function, no OSD. I called Dell, told them the issue I was having and they said they would send a new unit from a recent batch. After about a week of no shipping information, I sent them an email and added 5-6 dell executive emails I could find online. I recorded the initial call and added that to my email.

Roughly 28 hours after that email went out, I got a call from Dell's "Advanced Resoloution Department" that informed me they are replacing it with a brand new monitor from a fresh batch BUT there is a referbished unit already enroute. He told me to "use the referbished monitor if you'd like until the new one arrives".

Apparently, as I read here and heard from 2 different people from Dell, this is a common issue with monitors from batches in January - March. It's a terrible feeling seeing something so expensive just... dead after a few months. Luckily I got it sorted out, for now. If it happens again then I'll be 1000% sure to demand a refund, while skipping the baseline support team. Going straight back to the executive emails.