400 bulbs in 600 ballasts?

Sure its been said but NO take it from the one who didn't bother to read the box and put his 400 into hos 600 all u will achieve is buying a new bulb. The ballast was fine and now I don't change shit in the room when sober

during veg, I put a 400 watt halide in my 600 watt digital ballast, but I only run the ballast at 50 - 75 percent power, works fine for me.