Hi all,
Just joined the forums cause I am planning on starting a Car PC project. Sorry in advance if my questions are a bit obvious, but I am totally new to this.
Before I go all out on a car pc I want to do a dry run using my laptop. Therefore I need to be able to power my laptop in the car. Later on I will want to switch my laptop for a mini-itx system. My question is what would be better. An invertor or a DC-DC connection. From what I understand an invertor will allow me to plug in standard household devices, i.e. a laptop. However, I've also heard that EpiaMII boards can have a DCDC connector which means they can run straight from the cig lighter loom. The lilliput 7" Touch screen can also run from 12v. Basically my questions are:

Is 12v enough for several devices?
Will either option allow power up and down with the ignition?
Are there any major pros and cons of either I should consider?
Which is the best for power consumption, as I would like to be able to run this in the car when engine isn't running for the best length of time?

Thanks in advance.