Im Stumped....PLEASE HELP!

ok so i woke up this morning. i go downstairs and my desktop is on standby... im like wtf...i dont put it on standby, so i try to turn the power on, and nothing happens... just that blue, circular E flashing on and off like its in standby... at this point i dont know what to think... to i unplug it from its power supply. the light is still flashing for about 10 seconds even though its disconnected...remember people this is a desktop with a battery soo small all it can do is keep time...like a watch... so after it stops flashing...i plug it back in and turn it on...or attempt to... ALAS! it comes on for about half a second then goes back into seemingly standby mode....wtf....still no response from the power button...i opened my computer to take a look inside....nothings wrong...this is a perfectly healthy computer...or as it seems...the only part i cant see is where my power cord plugs in...it heavily gated off for safety issues i think... and it would require a lot of trouble to open... im wondering if any of you know what the problem is. im sending this from my laptop...

i have an emachines mostly custom built be me and my uncle...

model is emachines C6415

if you need to know more i can tell you but i dont think the other information is important...i do beleive it has something to do with the battery or the built in power brick...