1Gb/s ethernet but very very slow

[kempiedempie]

So, some time ago my Powerline adaptors broke, so my ISP brought new ones a few weeks ago (don't know what brand, just has my ISP's logo) but lately my internet has been going slower and slower and now it's at that point were it just won't load even though it says I have internet! The ethernet's properties says it's a 1Gb/s connection but yesterday it wasn't very fast and now, today it just doesn't even work anymore! and I don't know hat I should do, I tried resetting and rebooting everything and stuff but nothing helps and the ethernet icon in the windows (10) task bar doesn't show any problems!
Please if anyone know what the solution is, tell me.
Thanks!

 

[Alabalcho]

Where are there PowerLine adapters connected - on ISP link, or between the modem/router and your PC?
When you ping your router, what results do you get?