I am in the process of upgrading my stock system to having a 15" LCD screen, an Xbox and a 12" JL stealth sub. I am sure I will be watching some movies/playing games while parked or sitting in traffic.

What repercussions on my battery or alternator if I am running my system off or in idle? Is there a need to upgrade? Am I being completely paranoid?

 

UPDATE:

I haven't tested the Xbox and LCD screen in my truck yet, but I was driving around in my 'beater' car. It is an '88 camry (4 cyl, 4 door). Couldn't get my DC to AC inverter to work when I was parked, or when I was sitting in traffic. When I was cruising on the freeway it was doing fine. I got the inverter at Radio shack for $69.99. When it didn't work when I was sitting parked, I almost took it back. After a more thorough reading of the instructions, I realized it is set up to shut off if there is too little voltage supplying it (11 volts for instance). I might just need a new battery for my car.

I plan on trying the set up tonight in my truck. I think it should be okay, if not - I will probably be buying an extra battery.

 

well your system isn't two much of a power draw but it wouldn't hurt to upgrade the battery to an optima yellow top deep cycle.

 

Neither the LCD, X-Box nor the 12" sub will make a significant difference on your electrical system draw. What will make a difference, however, are any amplifiers you add to power that big sub or the rest of your system...

Idling, your alternator should still produce ~13.8 volts into a fully charged battery. However, if you have a large electrical load and a battery that is on it's last leg of life, you may experience discharge when idling.

I have 2 pretty large amps in my 'screw and have not had any problems with discharge...