Car DIES when driving! HELP!
I'm at my wits end here, I can't take it anymore. Recently I installed a sound system in my 1998 Ford Taurus. First off, the system isn't too big the subs maximum output is only 550W. So everything is installed so I take the car out on a drive and I'm driving around for about 20 minutes and all of a sudden my lights start getting dim then I lose power steering and the gauges and stuff stopped working. So I call my friend to come and help me jump it so I did and the car only ran for a minute more before it died again so I had to get it towed home. So I figured I'll charge the battery overnight with one of those 12v battery charger things so I did then I turned off my sub woofer and head-unit and I tried to drive it and it happens all over again.
So in frustration I headed to Advanced Auto and purchased a new battery (Optimum Red top) and a new alternator. So this time I thought it was all good and this time it lasted for about 35-40 minutes of driving time this time because I guess the battery is higher quality. What could POSSIBLY be wrong?! I don't understand.
Oh yeh and by the way before it's about to die the car starts to beep in slow intervals.