I don't know what causes it. Is it a updates or what, but for some reason my Solidworks works much slower with big assemblies as earlier (about weeks ago). I ran the performance test and the reults were these:

After that I ran it again immediately. The chages were that Graphics were 120sec and Processor 0.9sec, are this kind of variations normal in test? I have a MSI GE72 QD Apache pro laptop. I also noticed that when I work, the CPU in task manager never goes above 20%. Also I noticed that when working with big assemblies, it is very laggy to rotate the assembly (with middle mousebutton) if you do not select anything. If I select any part or face the rotating gets much much faster. Is this normal? If I have selected nothing and try zoom, it can take up to 5 seconds just to zoom in one step. 

As I recall I didn't have these problems while ago, now any tips are more than welcome to help me.