Ouch.. A power surge can cause unseen damage that may or may not stop it from functioning.
First things first, what type of video card is it? Have you tried a different video card? It may not be that your video card is damaged, it may be that its unsupported or has other problems with that mother board. Also, I would try a different video card and if it works, update the BIOS and then try plugging your old card back in and see if it works.
Many newer 4x/5x motherboards, depending on the BIOS/components, will turn off after you first turn it on, and then power back on automatically so this is expected behavior.
Thanks for replying. The video card was working fine with the older motherboard. It's in the PCIe slot- a GeForce 7600 DDR2 512mb ram. Has a fan, but doesn't require extra power from power supply, it runs off the mobo. Unfortunately, I don't have another video card that is compatible with this mobo to try out. I've tried booting without the video card just to get an error beep but don't even get that. It does exactly the same thing- turns off after five seconds, off for ten, then turns back on by itself and stays on until I turn it off. No beeps or anything. Frustrating.
The only thing left after the power surge is the ram (other than video card), which worked well after the surge. I've also gone through each one, testing one by one. No change.