LAN speed dropping from 100 to 10 mbps

mike_232

Commendable
Jul 22, 2016
2
0
1,510
My network is set up like this:
8IJntzx.png


Computers 1-4 work fine however the router seemingly randomly drops computer 5 to 10 Mbps and will sit there until restarting the computer. Sometimes it does it multiple times in a single day and other times it works fine for a week straight. The other computer connected to the switch still has a 100Mbps connection to the router and the 2 computers behind the switch still have a gigabit connection to each other.

I've already tried directly connecting to the router, using different ports on the router and using different cables but the problem is still there. I made sure I have the newest drivers and have tried forcing the speed to 100 Mbps in the driver settings and tried auto negotiation but the speed still drops.

I've also tried other computers using the connection this computer is using and they seemed to work fine.

Specs:
ASRock z77 Extreme 4 motherboard
Intel i5 2500k
Windows 10 (problem also existed under Win 7)
Using onboard LAN connection

Any help would be greatly appreciated, thanks.
 

mike_232

Commendable
Jul 22, 2016
2
0
1,510


Sorry, forgot to mention that the switch is connected to cables going through the walls which I believe are only Cat 5 and too long to get gigabit speeds.
Comp 1 gets gigabit to the router, comps 2 and 3 are limited to 100mbps by their NICs.

Still even when I bypass the switch and that bad cabling in the walls and connect directly to the router with CAT6, I still have the same problems.