crunchbang won't detect external monitor

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http://crunchbang.org – ^pretty much the title.I installed #! sucessfully, and after the install I was happily using it on my netbook connected to the external monitor. I was happy with it, the netbook screen was off and the display was on the big external monitotr. All I really did was update, browse the web, and changed some preference settings and wallpaper. But after I rebooted, crunchbang no longer shows up on my external monitor, which is blinking right now the way it does when it's getting nothing.So I look rather silly typing on this big keyboard connected to a tiny screen U^_^anyway...help??? (HowTos)