Looks like ES is finding support at 830, but I'm not sure it'll hold. Today's a Monday so if there's another big down day it's most likely today.
Also today is the last Monday in October, so there is hope for a rally this afternoon or tomorrow to take us into November and the presidential election.
That said, 775 is definitely a possibility for ES.
This Monday is so far gap down when the previous close was also down. On the last 4 occasions of Mondays being gap down with the previous close down, the Close on the day has been between 20 to 165 points down on the Opening Price (9.30am YM).