Ethernet on desktop completely destroys internet connection

[Muffinstumps]

I had posted a thread a while back talking about my rather annoying "ethernet issue" but with further investigation I determined it was not an Ethernet issue but a desktop issue. This is what has lead up so far. About a week ago my internet connection became unbearably slow to the point where it was almost unusable. I unplugged all Ethernet connections from our modem as a ditch effort to improve the network and it actually had! The internet was up and running as it always has. But, now every time I plug the Ethernet back into my desktop the internet just halts and wont work again until I unplug it. I thought this could maybe be a Ethernet issue at first but now I realize that if I plug the ethernet cable into my HP laptop it connects to the Ethernet right away and the internet still works as it should. I have retried all of this multiple times but I always get the same thing. Plug it into desktop and no internet, plug it into laptop, working internet.. I have done multiple virus scans and removed all "Potential threats" from said desktop. I have even updated and reinstalled the latest ethernet drivers. The ethernet cord is running straight from the modem so it couldn't be that a mouse may have chewed the wire to it because the wire is visible if you look hard enough and there are no physical signs on damage. Maybe it could be some sort of priority setting? This issue is really starting to push my buttons as my desktop is my main PC. All help is GREATLY appreciated!!

 

[BadActor]

Ethernet adapter failures are common on motherboards, but I've never seen one affect an internet connection that way (I'm assuming other devices get no connection). It's easy enough to test though if you get a cheap PCIe or USB to Ethernet adapter. You can also try resetting your IP stack and see if that helps. Also have a look at your routers QoS settings.

http://www.thewindowsclub.com/reset-tcp-ip-internet-protocol

http://www.howtogeek.com/75660/the-beginners-guide-to-qos-on-your-router/

 

[Muffinstumps]

Ethernet adapter failures are common on motherboards, but I've never seen one affect an internet connection that way (I'm assuming other devices get no connection). It's easy enough to test though if you get a cheap PCIe or USB to Ethernet adapter. You can also try resetting your IP stack and see if that helps. Also have a look at your routers QoS settings.

http://www.thewindowsclub.com/reset-tcp-ip-internet-protocol

http://www.howtogeek.com/75660/the-beginners-guide-to-qos-on-your-router/

Sorry for the late response. This problem has been fixed. Turns out my computer was downloading a big windows update in the background which was the source of the slow internet. It has been fixed now. Thank you