Need help diagnose a network problem.

[kogo50]

About 2 months ago we upgraded are internet from 10mbps to 20mbps down and around 2 or 2.5mbps up. Around the same time I notice that I wasn't getting the 20Mpbs that I should. I notice that my nic was running at 10Mps even though it is a 10/100 nic. So first thing I check was my drivers because I recently updated them. I decided to roll back the drivers and then that is when everything got messed up. My nic was running at 100Mbps but webpages were loading slow but things like YouTube and downloads were running at the full 20Mbps. I ran a speed test and it turns out I was getting almost no upload. Its was low enough that i would have to refresh the page 5 or 6 times to get it to go through. I updated the drivers again and no change. I didn't really do anything about it because I was rebuilding my computer. I just rebuilt my computer and the same thing. This time the nic was running at 100Mbps but no upload speed at all. I restarted the router and no change. Something I did notice was the light on the lan port that my computer uses is amber and according to the manual that means that a 10Mbps connection is going in to it. A green light means a 100Mbps or a 1000Mbps is plugged in to it. My first thought is the cable used to connect my computer to the router. It was install by someone a few years ago. I'm thinking it must be a 10Mbps cable and that the router is trying to compensate for it by giving me the full download speed but no upload speed but I have never heard of this or read about it. Does anyone have any ideas?

Hardware involved:
Mother board

ASUS Sabertooth X79 LGA 2011 Intel X79 SATA 6Gb/s USB 3.0 ATX Intel Motherboard

Router

Netgear n600 WNDR3700v3

Cable

Some type of Eithernet but specific type unknown

Software involved:

Windows 7 64 bit

ISP:

Atlantic Broadband

 

[Emerald]

It almost sounds like you have a bad cable.

CAT3 cables are rated for 20Mb/s full-duplex

you should be connecting at 1Gb/s between the PC and the router