BLACKOUT

Can someone tell me how to make windows run with out a monitor?

I got my system all set up today, just have to install it in my car, so I so I unplug all the things that wont be in my car (mouse, monitor), and use an amp meter to find out how big of an inverter I need, turn on my comp (found out it runs at .9 amps max, runs at .4-.6 most of the time, anyway), and I here it beep like 4 or 6 times, I am like ok, so it knows there isn't a monitor no big deal, so I let it go into windows, but windows never loads (I knew this because winamp should have been playing if it loaded all the way), so I plug the monitor back in, and there is an error message on the screen saying my vga addaptor is not set up right or something of the sort, so I restart with the monitor pluged in and it works fine, so I was messing around to see what I could do, I found out that if I unplug my monitor from the wall (i.e. power), my comp will run fine, but if I unplug the monitor cable between the comp and the monitor, from the monitor (in the back of it) or from the back of the comp, it will beep at start up and give me the error. I konw some of you guys run windows and don't have a monitor in your car, can you tell me how to do that, this is the last step I need before I install!
Thanks for any/all help
--BLK

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