Did you just let it sit when the light went off for a sec? Or did you panic and try to reset it immediately?
Yes you have killed your motherboard
Basically it's brain dead, During the process of flashing the bios the old one is deleted and the new one is programed in. The process got interrupted (Might be from any reason, power fluctuations, user interruption, wrong bios) but it has no brain anymore therefore it's dead Jim.
Don't panic quite yet though. Is it under warranty? Call and see if your warranty covers this. Usually the company can recover it for you. REMOVE your harddrive BEFORE you send it in though... Most of the time you'll find that when it comes back all your info is gone.
Also try taking the battery out and unplug it then leave it over night (If its not under warranty then find and remove the CMOS battery too) and hope the darned thing will reset itself. I've seen it happen.
Remeber when flashing BIOS on a laptop make sure your battery is charged and the laptop is plugged in and DON'T touch it untill it says it is done. Disable your screensaver too.
When you call Compaq just tell them it went dead and you have no clue why...