What is your speed with a known good cable. It could be possible that the new cable is just not capable of running 1Gbps
Cat 5 is good for 100mbps 5e is good for 1000Mbps 6 is good for 10GBps, If I were closer I would use my cable certifier to ensure you are getting 1Gb through the new patch cable.
if you download something via Steam or bittorrent what real download speed are you getting?
I hope that's not the problem. The cable was advertised as 10Gbps capable. It says it's a Cat6.
It should be good then. Unless it is terminated incorrectly. However if it is Cat6 you should be good as there is a + spacer in between the pairs so you should have 0 Cross talk. Can you transfer a large file between 2 machines on the same network?