[SOLVED] there was a humming noise from my PC and now it suddenly stopped. what is happening actually?

[using google in BSOD]

this one thing scared me a lot.
i'm afraid something bad will happen.
there was a humming noise coming out from my PC. it vibrated my table when the humming noise is on.
and suddenly, the humming noise gone. when i opened the left panel, everything seems fine. nothing stopped.
so, what is happening?

additional information:
my PC suddenly becoming slow and restart itself minutes after the sound gone.

 

[using google in BSOD]

i was just using google chrome.
and suddenly, my PC restart and the CPU fan suddenly running at highest speed the returning to normal speed.
the temperature was 40 degree celsius . which is not really that hot.
and it all happened after i changed my:
-motherboard
-PSU
-RAM
-adding ssd

anyone know why?
thank you!

 

[Phillip Corcoran]

You reinstalled Windows after changing the motherboard?

If you didn't, that can lead to all manner of glitches and unexpected events.

 

[Phillip Corcoran]

Full system specs please, including PSU make & model

 

[using google in BSOD]

i've taken a look at the entire PSU. but it doesn't show the name of the model
cpu is core 2 duo e7400
ram is 4 gb ddr3
gpu is gt 730 2 gb ddr3
ssd is v-gen 120 gb
hdd is hitachi 500 gb
additional (external hdd) is dell 1tb. detected but not showing in disk management

 

[using google in BSOD]

i reinstalled it.
but windows 10 seems to be risky if i try to run in this pc since windows 10 will have a BSOD easily.
so i installed windows 7 ultimate

 

[using google in BSOD]

after i found out, it was my PSU fan stopped rotating.
should i change PSU?

 

[using google in BSOD]

ok, i've found the solutions:
1.make sure you plugged the PSU cable properly
2.unplug any unnecesary external devices like ex.HDD, incompatible external hardware,etc
3.if there is an internal storage device that doesn't work anymore, get it out.

that's all. my PC is now healthy