How are you testing the speed on your PC? What motherboard do you have?
And do what Ganoncrotch suggested. We need to see a traceroute to Google (preferably their DNS 188.8.131.52) to make sure your packets aren't going through poorly optimized routes.
That's also really strange your speed dropped on a Cat7 cable. How far is your PC to your router?
It is windows 7 so I can't use any apps. Well most, I did find a windows 7 speed test app. I don't think it works though - it always is under. Like just now it did 135.
Otherwise I use http://speedtest.att.com/speedtest/ which just put it at 304.
My PC is right infront of my shelf with it. Infact when I take it off the shelf to put it straight up - I put it on my PC. They are that close.
1 <1 ms <1 ms <1
2 21 ms 2 ms 1 ms 76-220-100-1
3 2 ms 2 ms 2 ms 184.108.40.206
4 18 ms 15 ms 16 ms 220.127.116.11
5 13 ms 13 ms 13 ms 18.104.22.168
6 14 ms 12 ms 12 ms 22.214.171.124
7 13 ms 12 ms 13 ms 126.96.36.199
8 13 ms 13 ms 12 ms 188.8.131.52
9 13 ms 13 ms 13 ms dns.google [184.108.40.206]
I tried the cat 7 on my PS4 and it also dropped down to double digits. I plugged it into the AT&T box, unplugged the ps4 one (which is only two feet away) and plugged it in. Did I need to plug it/reset it/press the button any time I plug the new cord in?