Computer Lights and Fans Come on When Plugged In

[Whiteysureshot]

Ok, so i was watching tv tonight when i heard my computer sound like its coming on, i looked behind me and saw that the computer lights and fans were indeed turned on, but no display was on monitor at all, i tried to shut the computer down with a cold turn off ( pressing the power button for 3-5 seconds). The computer did not turn off forcing me to flip the master switch off. I opened up the case and took out my RAM cards and set them back in, I did the same with video card. I had the computer for 2 monthes off of newegg and got it for $1100/ gaming computer. I have never had a problem with the computer until now. Whenever i plug the power cord in the lights and fans come on and the only way to boot it into windows is pressing the power button again (it then gives the 1 beep and turns on). I went into bios as soon as i was able to boot and looked over the settings then i restarted the computer thinking i fixed the problem, but it does the same thing. I am beginning to think it is the PSU because when i just barely move the power cord comp shuts off. Just in case the booting is complicating ill go over it again

1. I plug computer into out let and immediately lights and fans turn on ( computer should be completely off)
2. When i try to turn in off by power button it wont shut off ( i have to use the master switch)
3. When lights and fans are on and i press the power button as if i were to turn it on it boots up no problem.

One more addition I do still have the warranty for the computer so if all else fails i could send in for replacement, but lets make that just plan B and see if we can find a fix instead.

Also im only 14 so dont use extremely high tech language, but i do know terms and parts to a computer.

 

[gary1]

Did you build it yourself, or is it prebuilt.