Dell Precision 5540 RAM upgrade from 2666 MHz to 3200MHz

I have a Dell Precision 5540 and I've been trying to find out if it can support 3200 MHz RAM speeds. From what I could find so far the specs given by Dell are 2666 MHz only, without mentioning that this is the only speed or whether higher/lower ones are supported. I also tried to look up some motherboard specs, but I could not find anything regarding this aspect. However, on their website section for upgrades for this specific model they do list RAM upgrades with speeds up to 3200 MHz, which hints at the possibility, but as I could not find anything specific I'm still in doubt. Does anyone know if this laptop can run RAM speeds of 3200 MHz?