So could i do this:
Wire one end of a Micro Shutdown Controller to the cigarette lighter 12V line and the other end to a Laptop Car charger. Then wire a switch somewhere on my dash to power the laptop (or use a wake on lan or usb device setup or something similar).
You said that "an inverter is generally a poor solution". In the setup i mentioned above, would the "inverter" be the "car laptop charger cord"? And also you said you wired a 120W power supply to your battery? Isn't the battery 12V? sorry about all my confusion, i'm not very knowledgeable with automotive electronics.
for automatic startup, check your bios settings and see if you have an auto on with power or a similar setting. This will start the 'puter when you apply power to it. Some bios have it some don't.
For shutdown, set the power settings in xp to shutdown when running on battery power for 5 minutes (or howeer long you want).
Just get the 12v adapter for your laptop and wire it into the car properly and all is good.
For once you have tasted flight you will walk the earth with your eyes turned skywards, for there you have been and there you will long to return.
Leonardo Da Vinci
You'll get a lot of good advice as to what you should do, but it will be up to you to decide what is within your budget and works the way you want it to.
My advice is to search a lot of threads on mp3car.com and read what other people have done and the problems they've encountered. That will help you to decide what works and what you should do for your own project.
Ah ok... thanks a lot guys!
GreatWhite, I've scanned through my BIOS settings and can't find the boot options anywhere. I know on other computers I've seen "wake on lan" or similar options but I can't seem to find anything like that on mine.
And thank you, Computergeek, for the diagram. Your post was very helpful as well.