Question System lagging

[Sonny1989]

Hi, for the past few weeks my PC started running slow while downloading. Every time i download using steam or even when i run internet speed test my pc freezes and lags. I ran series of HDD and SSD tests and it all seemed fine. I also switched all my RAM sticks and I was getting the same problem.
My specs:
I7 4790k
AsRock extreme4
4x4gb RAM
Msi 3080
Corsair RM650 psu

What could be a problem? Please help

 

[rgd1101]

ssd or hdd?

 

[Sonny1989]

Ssd samsung Evo 840 120gb
Hdd WD caviar blue 1tb

 

[rgd1101]

when you download, it downloading to the slow hdd?

 

[Sonny1989]

Yes, but then when i download through website, like for example i was downloading programs for testing no lagging at all, only when i do speed test, download on steam or even when i preview a video on youtube or netflix(when you drag your cursor onto the video without clicking)

 

[Sanders94]

Have you checked your drivers, are they all up-to-date?

 

[Sonny1989]

Yes, i also updated my bios