computer is not working, I've tried almost everything

My computer hasn't been working great for the past few months. The time is never right and my computer always shuts down randomly, no warning it just shuts down. Every time i power it on after it dies it takes a while, and it flashes 1 white 3 amber. I've replaced my battery, replaced the cmos battery, run countless tests and the problem persists. I honeslty have no idea whats wrong. My computer is only about 2 years.