According to the official PC Requirements list, Watch_Dogs needs at least 6GB of RAM. Well, today I can reveal that there won't be any hard lock mechanism preventing users from playing this game, even if they only have 4GB of RAM. In short, PC gamers with less than 6GB of RAM will be able to launch the game.

There might be some swap issues when the game loads more data, but there won’t be any lock similar to the one found in the unpatched version of Call of Duty: Ghosts. Watch_Dogs releases on May 27th!

Arkaprava Biswas: I am only asking that will it RUN smoothly on high settings with 4 gb RAM and a gtx 780.. :'(

Jonathan Morin (Creative Director of Watch_Dogs): 4GB is lower than min specs. It might run if nothing else is running, but when it swaps to your hard drive it will lag.

https://twitter.com/Design_Cave

Watch_Dogs Will Run With 4GB RAM