Separate control unit from Leds i am using one adapter (12vDC 2A) i want to be able to power led strip with it plus the control circuit the problem is that the atmega328 reboots but when i only powers up the led strip with that adapter and power the control circuit with a independent 5v adapter every thing seems to be alright but i cannot do that in real world i need to get advantage of the same adapter i attached a picture of what i am doing right now help me to fix this
i am using 7805 regulator to reduce the 12v to 5v
Why not use the barrel input connector and input 12VDC there, the filtering etc on the board will help. Also as dandavis stated you need a bigger power supply or remove about 1/2 of your LEDs.