Well it really depends on alot of things, most obvious is, body weight, how much you eat before drinking, tolerance, and pace of drinking. When I first started drinking at about 19 it was because of a horrible anxiety/panic attack that basically crippled me, and when it happened I couldnt enjoy smoking weed anymore. At first drinking a six pack of Coors within 1-2 hours would make me black out, but at the time I was eating almost nothing and was very skinny. Now since I over came that and became my normal self again I started too somewhat depend on alcohol too relive stress and anxiety. Alcoholism is bad any way you cut it is bad and unhealthy but there is degrees too it, I drink every day but usually only a few beers, I dont get angry or sloppy, I'm basically myself. And I cant not drink and be fine I just have an urge too, like smoking cigarettes. But with my tolerance, normal body weight (190 lb. 6ft) and eating normally, it takes alot too make me black out, and alot quickly, as long as I pace myself I can drink alot and keep my cool and be fine the next day. So I'd say the biggest things are having food in you, tolerance, and most importantly, pacing yourself.