The computer worked fine yesterday but today when i tried to start it nothing happened. I tired removing the 4 pin connector that goes to the cpu and the computer starts but i get no picture or post or anything obviously. But it "starts". but Is it a bad power supply or is the motherboard bad?
This could be a problem with the power supply, the processor, or the motherboard. The only way to be really sure is to swap components with known working ones. (It's pretty unlikely to be anything else, for whatever that's worth.) If you can provide more detail about what exactly the components in the machine are, I could probably speculate as to which component is most likely, at least.
(I assume you reconnected the 4-pin afterwards, just to rule out the possibility that it was loose or something.)