Depends totally on the temperature of the room, and how high above the chicks the bulb is hung.
To give you one data point, in my 52 F basement, for day old chicks in a brooder with no top and 1.5' high walls, I start them with a 175w bulb about 16-18" above the floor, and go on from there (raising bulb and/or lowering wattage as they get older)
READ YOUR LIGHT FIXTURE'S LABEL, it will tell you what's the highest wattage bulb you can use in it. Clamp-type lights often have a maximum of 60 or 100 watts, but go by whatever your label says. DO NOT EXCEED the labelled wattage unless you want fire engines and insurance claims.
Usually you want to have the brooder light on for 12-24 hrs before putting chicks in, to let the bedding etc thoroughly warm up.
Good luck, have fun,
Pat