PC: Won't Turn On

Question

Earlier in the day at 4pm I went to a friends to check out the PC. It worked fine, I then brought it home removed GFx + Ram from the new one but then decided to put them back in ((long story you wont need to know)).I then come to turn this new PC on at 8pm and now I am just getting a black screen from my monitor and -- 1 One second Beep and 1 Three second beep.Please help.