Question Internet connection dies when downloading games on my desktop PC, but other devices don't have the same issue on the same network ?


Apr 9, 2019
Hey everyone , thanks for reading .

My problem:

When I download games from Steam , for example, it downloads at full speed, no problems, then the speed starts to drop quickily and the connection dies, every device connected to the modem lose internet connection as well. This only happens when downloading from Steam or Epic or Chrome in my desktop PC . Sometimes this happens during the first few megabytes , Sometimes the connection comes back on 2 or 3 minutes later, sometimes I have to reset my modem.

My setup info:

Internet connection DL speed is 100 Mbps (Speedtest DL speed peaks around 114) , my Modem model is Sagemcom Fast 3686 V2 CVA , my Desktop pc has a Gigabyte Aorus B365M motherboard and I'm using an ethernet cable connected from my modem to my motherboard directly, no router, Im using Windows 10 64 bits.

What I have tried so far:

  • Limiting download speed : Didn't work, tried limiting it as low as 40 Mbps , still crashed.
  • Downloading from another laptop over wifi and wired: It worked fine, up to 100 Mbps-ish for a few minutes, no crashes.
  • Changing DNS to manual and set it Google's DNS, no results.
  • Ipconfig renew, flush etc. commands as admin, didnt work.
  • Network reset from windows' 10 control panel then reboot, no results.
  • updated my LAN drivers, nothing.
  • Connected my android phone and used USB Modem option ( It gives my phone's WIFI internet connection to my PC over USB), it downloaded at full speed then crashed , same problem.
  • Downloading while in Windows 10's Safe mode, same problem.
  • Switching ethernet cables and modem LAN ports.
Extra Info that may be related to my problem:

I just moved from home, In my previous place I had a TP-Link router where I configured DHCP reservation so it gave my Desktop PC (the same one Im using right now) the same local address everytime (it was . My actual modem's gateway is,same as my old TP-Link .
I noticed that my PC is still getting that address , even though I didn't configure DHCP reservation in this modem, so looks like my Motherboard stills remember its old address and ask DHCP for that adresss especifically. In windows 10's network settings, IP is set to be obtained automatically.
On the other hand, I tried to set a static IP from windows (something like , ipconfig says I got that address , but the same problem persisted, so I'm not sure if that could be the problem.

I appreciate any help or ideas , thanks in advance.
Last edited:


May 7, 2014

If you start off high and then gradually crash it sounds like energy efficiency crap.

Open network controllers (open start and type ncpa.cpl and hit enter)
Right click ethernet controller > Properties > Configure > Advanced >

Disable the following;
Energy-Efficient Ethernet
Gigabit Lite
Green Ethernet
Interrupt Moderation

Depending on your router/cabling you may or may not be able to disable Interrupt moderation or gigabit lite so do them one at a time and make sure you don't lose connectivity or know which one to revert if you do.

Hope this helps


Another thing you can do is to use Task Manager or Resource Monitor to observe system performance.

Use both tools but only one tool at a time.

Determine what, if anything changes when the Steam download speed drops.

First open a Task Manager or Resource Monitor Window and observe while the computer idles.

Leave the window open and sized so you can continue to watch.

Start a Steam download - good chance that you may see what happens.

Observe performance both with and without the energy efficiency options enabled.