Why is my PC lagging?

[knightofcydonia98]

All of a sudden my PC has started to lag. My specs are:

-AMD Phenom 2 X4 980 (Quad 3.7 ghz)
-Radeon HD 6970
-8GB DDR3 Ram
-1x500GB HDD
-1x 250GB HDD

The specifications of my computer surpass the requirements for the games I want to play. For example: Grand Theft Auto 4 recommends a Phenom 9850 and an HD Radeon 3870. But yet I achieve 40Fps max which I cannot play with. Another example is Eu Truck Simulator 2. It recommends an Athlon X2 dual core and a Radeon HD 6670 but yet it stutters like mad. But it's not just gaming that my PC is struggling with at the moment. Browsing the web often causes the machine to freeze for at least 1 minute. Also, for example if I log into to Steam and while it's initializing I close Skype, the machine locks up for again 1 minute.

It is getting increasingly annoying and I would appreciate a solution to fix this problem. The graphics card achieves high scores on Passmark along with the CPU.

Thanks.

 

[aonor]

This might have to do with more of your Operating System then your computer parts. Get more advice before reinstalling OS.

 

[knightofcydonia98]

That didn't help, in fact it made it worse. My data is gone and the system takes a horribly long time to get to the desktop.

 

[Guest]

you are using wifi??

 

[knightofcydonia98]

Yes I am using wifi why?