I expect this to happen more and more.
Just recently a member found Comcast throttling Netflix speeds to under 18 megabit. This would be OK for 1080 video but short of what's needed for 4K UHD.
Your PC may be just fine but given Net Neutrality is no more, all bets are off you will get full speed today.
Basically today I went on speedtest.com and it shows that my internet speed should be around 8 mb/s however when I'm downloading (anything) I only get around 100 kb/s and it fluctuates from 12 kb/s to 600 kb/s and drops back down immediately and the speed never goes over 1 mb/s. I've tried everything to fix it and the speed is still so slow. Please send some help. Thanks. In addition, I downloaded an app called iolo system mechanic to clean my laptop don't know if that has something to do with this slow speed or not. Thanks