I've been trying to troubleshoot some problems with setting up SLI on my PC, and after attempting to clear the CMOS by reseating the battery, the computer won't start up at all. It was working completely fine until the attempted CMOS clear, with the exception that I couldn't get SLI to work properly.
Now you can connect all the other components again and boot, let me know if works.
Is it possible that you left the jumper on the CLR_CMOS Header after you cleared it, and didnt remove it, as this breaks the mobo circuit and thats how the CMOS Is cleared, by cutting power to the chip, The PC Wont boot without a CMOS. Or atleast to my knowledge.
Clear CMOS works with only a button in the board, few years back the jumper was removed for that same reason, a lot of people forget to changed it to the original position.