My PC is running extremely slow maybe a Hard Disk or RAM problem?Help

[KAAIZER]

I found recently my PC is running extremely slow.I thought it might be a software problem so I reinstalled Windows and formatted C drive but no change.Its as slow like even a 240p video lags on VLC.I checked the wire connections ,readjusted my CPU heat sink.Nothing works.

I wonder if it is a RAM problem or Hard Disk problem as it might not be CPU problem because CPU dont ever die out.I need help urgent.
I have Corsair Vengeance 8gb,i7 4770 and ASUS Maximus Hero vi mobo.
Also my PC used to crash with Blue Screen saying PC ran into some problem but thats ok now.Also sometimes I used to get CPU overheating error thats ok now too.

 

[DeViL5o5]

you might want to check your CPU and memory usage via task manager or some other monitoring tool and see if there's an application slowing you down. You may also want to run some hard drive tests to see if your HDD may be failing.