Please help

[clarke23011]

my computer is randomly turning off rarely done it 2 times so far. first time it happen my screen turn black on me so i check on my computer i heard some loud buzz come from it. when i open it, everything was off but my HHD's. all my HHDs was spinning at full blast they was making a loud noise and when i put my hand on them shaking like crazy. when i turn on the computer after turn it off by a power supply. the same thing will happen my CPU fan and my GPU won't start but my HHD's will turn on. but i notice if i unplug my PSU for like 1 min it will start up a computer sometimes but what i have to do most times is keep turning it back on and off by the PSU switch till the fans and i hear beep from my motherboard.    

[Altecice]

Full computer specs?

[clarke23011]

AMD FX 4300

GTX 970 (i know it it is being bottleneck i am getting a money to get a i7 4970K in 5 months of so) 

760M-P23 MSI motherboard 

CX600M corsair PSU 

8GB DDR3 240 pin 1866Mhz 

windows 7 

[Redsun20]

my computer is randomly turning off rarely done it 2 times so far. first time it happen my screen turn black on me so i check on my computer i heard some loud buzz come from it. when i open it, everything was off but my HHD's. all my HHDs was spinning at full blast they was making a loud noise and when i put my hand on them shaking like crazy. when i turn on the computer after turn it off by a power supply. the same thing will happen my CPU fan and my GPU won't start but my HHD's will turn on. but i notice if i unplug my PSU for like 1 min it will start up a computer sometimes but what i have to do most times is keep turning it back on and off by the PSU switch till the fans and i hear beep from my motherboard.    

To me it seems like it is either (or both) the PSU or the Motherboard. Regardless, that does not sound good.