I recently acquired a CyberPower A108. for 3 days it was running fine. I had just added a second monitor, jurned on the screen saver, then took a nap. But when i woke up the coomputer was turned off and will not turn back on. Some people will a similar problem say their lights flash and fan spins for a minute but i get no response from the computer. There is power running through the computer because the usb mouse is still lit.
Try pulling the power cable out of the back, then pull the battery out for 30 min, stick it back in the same general direction it was before, and then plug the cord back in. Then try turning it on and see if that doesn't change anything.