Read what to scan with at http://www.cnet.com/forums/discussions/how-to-remove-pup-option-603542/#post-f742c795-5881-433b-a29b-6d758efe5cd3
The PC details are slim. I've found low disk space, too many antivirus suites, a hotspot shield and just bad hardware along with infected PCs.
Start with Grif's advice then review your machine's Speccy report. Members will look at it for you if you share. How is at https://www.piriform.com/docs/speccy/using-speccy/publishing-a-speccy-profile-to-the-web If those don't pan out you try some USB WiFi since the onboard modules can age and get wonky. Resetting the OS is also an option but many won't and you try the above first.
sometimes the internet will get really slow, allmost not working. when it happens, i restart the wifi on my laptop (only the wifi) and the internet starts working fast again. it happens alot, somtimes every 15 minuts. please help. ty

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