Mörtti, if you're using
Windoze, go download Belarc PC Advisor, which will generate a complete report on your computer system (internal devices, network speed, etc), without you having to manually type in everything here on TomsHardware.
Click here to get the tool, it's free, and it's been available for years. If you're using a Linux Operating System, get me the following outputs from Terminal:
netstat -a eth0
sudo ifconfig
I see you're in Europe, like myself. I also saw you hit 850Mbps for a blink, then throttled down to sub-200Mbps.
Shoot me a Private Message if you get stuck, I'll see you through. Greetings from The Kingdom of the Netherlands.
Live long, and prosper, friend.