computer barly turns on

My computer doesnt turn on all the time. I was using it and I had left it on over night. When I woke up my power supply was making some odd noises. I ordered a new power supply and got some ram while I was at it. The computer was still working with the old power supply it was some 450W power supply that came with the case it just kept making noises. I plugged in the new power supply a 580W Black Steel and the ram. Now the computer barely turns on. I have to press the power button then cut the power 10-15 times to get it to turn and some days it will not turn on no matter what. When it does manage to turn on everything is fine it doesnt crash its fast. I tried putting the only power supply back in and still does it. The motherboard is a PCChips A11G V1.0 its Socket Amd Am2. If you have any idea as to what would be causing it not to start please let me know.

 

Try resetting the BIOS.

Just to clarify, when you press the power button the system does turn on and you have to restart it several times before it will POST?

 

What is the EXACT make and model of the power supply you purchased?

 

@loserOlimbs

When I press the power button the fan on the heat sink starts to turn but stops and the led on the front of my computer turns on for a split second. The computer then becomes on responsive until I turn off the power supply/unplug it.

@win2kpro

The power supply is a CaseGears Black Steel 580W model BKS580.

 

Try reseating everything again. Pay special attention to the power supply, RAM, and where the CPU fan is plugged in.

 

I reset the cmos or whatever. I have switched the ram completely and I have switched my powersupply to my old one. But it still messes up. I have never unplugged the fans. They had always worked before. I have onboard video and recently my moniter has started to flicker alot. When the screen goes back to normal my vista has a little popup saying that the video has suffered a hardware failure. I'm thinking I should just get a whole new board what do you think?