Electric breaker

I'm planning on adding more lighting to my setup, and possibly another fan, how many watts is going to kill my breaker? They're all 120volts plugs. Should I plug a ballast into different outlets? Or the same outlet ok? I'm only running a 400 watt light a 120 watts are being used for my fan. I'm going to double I think. So..... total 1040 watts, through 4 plugs. Should I get extension cords and distribute to different outlets throughout the room, or just plug em all in one power strip?

The outlets are likely powered by the same branch. You might be pushing it if you're only using a 10 amp circuit, 15 or 20 amp circuit will handle it no problem(depending what else is on it). Check your fuse box.