I just built my first computer. Won't start right from the beginning. a light on the mother board is the only indication I get that power is connected at all . I am certain that the 2 12v connectors are connected to the motherboard properly and the PSU is switched on. With so little to work with I'm not sure how to toubleshoot this. I hope I just neglected something very simple.
Please post your COMPLETE system specs. My knee jerk response would be either underpowered PSU or CPU/RAM not properly seated. you need to give us some info to work with. Check all your power connections, and your header connections i.e. power switch. Reinstall your RAM.