i work out 4-5 days a week (no cardio) but if youd like do it its a great way to boost your energy/heart level. by running or doing any cadio will help you in the weight room!
over training will just get you ripped depending on how good your genetics are you might gain strength! i gained alot of strength from overtraining and everything just because i come from a long list of power lifters and body builders who all have good genetics!! i used to work out like you do and i didnt gain any size the only way was to eat so much and i got worn out!
work out monday,wensday,fri,sat,sun or dont work out sun. depending on your goals, do you want to be big or ripped