Is my logicboard Dead now? :(

Help,

i had changed some parts like battery, home button and Lightning unit. I pluged everything together, attached the screen and everything worked fine and i even called another fon of mine. so i was happy. but as screwed everything together (i always have my screws colored and numbered like on ifix it) so there couldnt have been a wrong screw :( i turned on the fon and just the apple appeared.

Normaly the Apple gets a bit brighter after 10 sec. but not anymore. It hangs a minute in this state then (and not earlier) the screen gets blue and it starts again with the apple until another minute is over :( and so on..

I attached as less parts as possible after that, like only the start button, battery and display but the same symptoms :(

(Ps. i tried two new batteries but the same result)

is my logic board gone now ???

what can it be ????

Im sad now !!!! :( :/