Modern motherboards are fairly resilient, but they’re not impervious to damage. So when your mobo appears unresponsive upon powering your system, it can cause momentary heart palpitations. Some mobos are pretty expensive, and even when they’re not, replacing one is more time consuming than other components.
Usually if you’re having problems with your motherboard powering on, you should look at the rest of your setup to see if there’s an issue. The following steps guide you through the troubleshooting process, starting with the easier and more common suggestions.
(And for anyone wondering: No, a CMOS battery can’t prevent your motherboard from powering on. Not with modern motherboards, anyway. That coin battery just ensures that your BIOS settings, such as boot order, fan curves, and the like, remain saved. It can’t hurt to replace it if you truly think it’s the source of your problems, though—they only cost $3 or so.)