I was having terrible lag spikes a week ago, bad enough for me to die by 1 mob 5 levels bellow me. It took me minutes to cast a single skill, so after some monitoring of resources I discovered that SVCHOST was sometimes using more than my internet could handle (But my internet is *** anyway

)
After some research I've found a guide on disabling SSDP Discovery, that, by others words, is responsible to find windows home groups. And I do not use this so disabling that helped more than I can tell.
Here it goes:
- To disable the "SSDP Discovery" service:
- Press WINDOWS + R and type "services.msc" in the search field and press enter.
- In the "Services" window, look for the following entry:
- SSDP Discovery
- Double click and set the "Startup type" as "Disabled"
- Click OK and close it
You might want to restart your PC after that to be sure the service is really stopped.
Hope to help someone with similar problems.