black screen Asus EeePC 1005HAB

I have an EeePC 1005 HAB, switch to lubuntu from WindowsXP. While trying to engage wireless I pushed Fn and all of the F-keys. Not sure which key (probably F4-8) turned screen black. Now it won't light-up. I have powered down, removed the battery, held power button, restarted and still only black screen. I have pushed the F-keys and Fn F-keys, still black screen. Any ideas?