newb, in car pc, avoiding disaster?

Here's a link to some DC power supplies/convertors as well: I have the M2-ATX http://store.mp3car.com/category_s/22.htm

Those computer power supply estimates may be bogus; power supply sellers are looking to sell you the biggest supply they can.     Before investing in an overkill inverter, measure the real power consumption if possible. There's gadgets that plug between the wall socket and an appliance, and give a readout of voltage, current, line frequency, power, and power factor. One brand is "Kill-A-Watt"; I bought one on eBay and it's a steal for what it does. Also, consider just how much computing power you really need. A good video card with hardware acceleration for video codecs has to be more efficient than laying all that work on the main CPU. If you haven't checked out the forums at MP3car.com, there's all kinds of knowledge there.Is this bass really strong enough?