Fairly new to Car pc's and have been reading a lot, but stuck on what way to go with for power.

Right now I have a Double Din, EQ, crossover hooked up to 3 amps 2 subs and 2 sets of 6.5 separates . The largest amp is 1500 watts for my subs then I have a 4 channel 600 watt for the front set of 6.5 separates then another 400 watt amp for a rear set of 6.5 separates. The vehicle is a Yukon and I've already upgraded the battery to a yellow top AND have 0 awg from the batter to my distribution block for the amps so my power seems fine, but I do have the occasional light dim when at full power during heavy bass tracks.

I have read most people use M4 or Opus and keep the load under 250 watts, but I just ready a review on an soundblaster external xfi and the guys has his carputer in the back of the truck connected via a 1000 watt power inverter.

Since I already have a huge draw on my current battery should I consider a 2nd batter, upgraded alternator, or both?

Also what are the advantages of running the pc from a power inverter? Since the yukon already has power in the back truck via a cigarette lighter connection if I used that it would allow me to connect an inverter and avoid having to redo my center console to mount the pc.