New 150/65 only at 94 Download AND Won't Work with Gigabit Switch

Question

I just had this installed today, converting up from the 35/35, and ran into these two problems:
1.  The 150 download is only resulting in a 94.87 Mpbs.  The installer originally said it must be my PC NIC card, but I do have a GB card, so there's does not appear to be legitimate reason for the shortfall there.  I tried to change the link speed and duplex from "auto negotation" to "1 Gbps Full Duplex," but then my computer no longer even could connect.
2.  The second issue is that I have always run my connection through a D-Link DGS-2208 Gigabit Switch because I have multiple wired ethernet computers in my office.  The installer wanted to test the connection speed directly through my computer (see above) and ran into problems, so I never even tried to revert to my original setup with the switch until he left.  However, when I did the Gigabit switch does not even recognize any activity when I plug the source ethernet cord into the switch.  It does recognize the connection to the PC and the port is lit, but no lights from connection to the wall.
Any thoughts on what the problems could be?  I've included the "additional details" from the Fios Speed test at the standard site (can't get any details from the high speed version):
Checking for Middleboxes . . . . . . . . . . . . . . . . . . Done
SendBufferSize set to [261360]
running 10s outbound test (client to server) . . . . . 42.90Mb/s
running 10s inbound test (server to client) . . . . . . 69.90Mb/s
------ Client System Details ------
OS data: Name = Windows 7, Architecture = x86, Version = 6.1
Java data: Vendor = Oracle Corporation, Version = 1.7.0_05
------ Web100 Detailed Analysis ------
Client Receive Window detected at 65340 bytes.
622 Mbps OC-12 link found.
Link set to Full Duplex mode
No network congestion discovered.
Good network cable(s) found
Normal duplex operation found.
Web100 reports the Round trip time = 6.78 msec; the Packet size = 1452 Bytes; and 
No packet loss - but packets arrived out-of-order 0.02% of the time
This connection is receiver limited 37.88% of the time.
Increasing the the client's receive buffer (63.0 KB) will improve performance
This connection is sender limited 61.7% of the time.
Web100 reports TCP negotiated the optional Performance Settings to: 
RFC 2018 Selective Acknowledgment: ON
RFC 896 Nagle Algorithm: ON
RFC 3168 Explicit Congestion Notification: OFF
RFC 1323 Time Stamping: OFF
RFC 1323 Window Scaling: OFF
Information: Network Middlebox is modifying MSS variable
Server IP addresses are preserved End-to-End
Information: Network Address Translation (NAT) box is modifying the Client's IP address
Server says [{edited for privacy}] but Client says [192.168.1.16]
Solved!
Go to Solution.

Answer 1

tdaignault wrote:
I tried to change the link speed and duplex from "auto negotation" to "1 Gbps Full Duplex," but then my computer no longer even could connect.
If your computer can't negotiate a 1Gbps connection, then that is what is limiting you to 94Mbps, which is about right for a "100Mbps" port.
There could be several reasons for this.
A bad NIC
A bad port on the switch
IMO, the most likely cause is a bad cable.  1Gbps requires all 4 pairs in the cable be connected.  If only 2 of the 4 pairs are connected correctly, you will get a 100Mbps connect, but will not be able to connect at 1Gbps.  Try replacing the cable with one known to work at 1Gbps.