100 Mbps Slowing Down When Gigabit is Present

[FactorOfLife]

Hi,

So a couple of days ago I built a computer for my brother. I also ran Ethernet to his room from the router. After this, my internet speed has gone down from 60 Mbps (full speed) to around 0.2 Mbps, even when his computer is not being used (still on). I did some diagnostic testing and found i this much.

1. He is on gigabit, I am on 100 Mbps

2. When limiting his computer to 100 Mbps (using a 100 Mbps USB 2.0 to Ethernet adapter), my internet works at full speed

3. His internet works at full speed on both gigabit and 100 Mbps

 

Any thoughts or suggestions on how to fix this? I had the idea of buying myself a PCIe gigabit adapter,do you know whether that will work or not?

 

Additional Information:

Our max internet speed from our ISP is 60 Mbps

I do not have a gigabit adapter that I can use for diagnostic testing

I do not wish to continue to use the USB to Ethernet adapter, it is currently being used elsewhere.

Both computers are using the same type of Ethernet cable (cat5e)

Our computers are the only devices i kept on the network for diagnostic testing

I am not using any sort of network switch on either of the computers (modem -> router -> computers)

We are both currently using the Ethernet ports built into our motherboards

 

Router:

Netgear Nighthawk R7000 AC1900 Router

 

My PC Specs:

Intel Core i5-4690K

ASUS GTX 770 2GB GDDR5

Corsair CX600 600 Watt Power Supply

8 GB Crucial Ballistix Sport RAM

OCZ Arc 100 240GB SSD

WD Black 1TB Hard Drive

MSI B85M-G43 Micro-ATX Motherboard

 

My PC Specs:

AMD FX-6300

MSI GTX 960 4GB GDDR5

EVGA 600B 600 Watt Power Supply

8 GB HyperX Fury RAM

Samsung 850 EVO 250 GB SSD

WD Black 1TB Hard Drive

Gigabyte GA-78LMT-USB3 Micro-ATX Motherboard

[Arty]

if you  have a nighthawk....just use wifi lol....

[DXMember]

get a better router

[FactorOfLife]

6 hours ago, DXMember said:

get a better router

I don't think you understand. It's a 1900 Mbps router. Simple math will show that it can handle over 30 computers at 60 Mbps.

[DXMember]

5 hours ago, FactorOfLife said:

I don't think you understand. It's a 1900 Mbps router. Simple math will show that it can handle over 30 computers at 60 Mbps.

well obviously it can't