i own a renault megane coupe sport 1.6 16v with air con and my battery light came on.... half an hour later the lights dimmed and engine died... i called the r.a.c and he said that my amp has drained the power and burnt out the alternator! my amp is only 500watt and 200watt subwoofer... hundreds of my friends who have cars have a standard alternator and MUCH more powerfull amps and systems.... my alternator gives off 90watt...... does this mean when i get a new alternator i cant have a nice sound system??? 