Half my network not getting full transfer speeds

[Jothay]

In my home I have set up a network that's a bit more complicated than most home users. The computers are connected as follows, see the notes about it. I have named several objects to make it easier to read this.

1. Cable Modem (50 Mbps Down/5 Mbps Up connection to the internet)
- Direct to Router and cable jack (coax), no other connections
2. Linksys E4200 Router. WiFi is active, though only tablets and phones connect to it usually.
- Connects to walk socket, line runs to attic and down into A/C closet where 16 port switch resides
3. Netgear 16-port switch sits in the A/C closet. All other wall sockets in the house connect to this using the same Cat-6 shielded cabling (from a 1,000 ft spool)

So here's the list of systems:
Room 1 (Master):
* Dell Precision M6600 laptop using the Gigabit Ethernet port on the E-Dock. This gets full Gigabit speeds when connecting to TheStorage. This connects to a 4-port switch then the Wall Socket (and thus, the 16-port switch). Also on this 4-port switch is an A/V receiver, an X-Box 360 and a PS-3.
* JothyWothy - Custom Built Desktop which has a Rampage IV Extreme Mobo, Gigabit NIC, gets full speed when connecting to TheStorage. This connects to an 8-port switch along with TheStorage (there used to be more connected here, but setup has changed) which then goes to wall and then the 16-port switch
* TheStorage - Ubuntu 12 File Server, which also does Torrents and other media sharing stuff. Same switch as JothyWothy then wall then the 16-port switch
Room 2: Nothing
Room 3: Mac Laptop using Wireless
Room 4: Spin Custom Built Desktop with a Gigabit Ethernet to wall socket to 16-port switch
Room 5: 2 Desktop computers (Onyx and TheKitchen), with Gigabit Ethernet cards are plugged into the E4200 due to troubleshooting, though normally they would be plugged into a wall socket that goes to the attic and 16-port switch.

Issue:
Some of these systems can reach full Gigabit speeds during file transfers with the share, others do not. They all report Gigabit but when you actually transfer a file it acts like 100 Mbit.
Systems that get full speed: JothyWothy, M6600 and Spin (sometimes)
Systems that can't get full speed: Onyx, TheKitchen and Spin (sometimes)

The owners of Onyx and TheKitchen are repeatedly getting all kinds of pissy with me because they can't get full speeds to the share and say its my fault there must be something wrong with the share. I need someone that can tell me what I can do to try and fix this. We've tried different cables (except running them through the walls, that's a huge pain in the arse) and Onyx/TheKitchen have both been plugged into a wall socket and the E4200 and they get the same issue. At all times, they still report 1 Gb on their network speed, so it's acting like 100 Mb but not saying so while at the same time I get full speed on JothyWothy.

 

[Saga Lout]

Hello and welcome to Tom's Hardware Forums.

On one of the affected systems, preferably one running XP, go into Control Panel>Network Connections, right click the ethernet connection and go to Properties. Under "Cnnect using", click the Configure button beside the device and then click the Advanced tab and on Media Type. I suggest changing from Auto to 100Mpps half duplex. If it's on that setting or another, change it to Auto. Apply and OK your way out then restart that system and see if speed improves. Another change may have improved things if that one didn't.

 

[john-b691]

First you need to see if its the machines or something else. I would either temporarily move them into the room and plug them into the 8 port switch. You could also take a long lan cable and string in on the floor just to test.

If it still does not work then at least you know you need to change setting in the machine.
If it works then I would first suspect that the house is cabled incorrectly. The most common cable problem is the pairs are not correctly matched. Check the ends of the cables and make sure they follow one of the 2 standard color patterns.

 

[DrRus]

What John said.
And check the network connection on the troublesome computers to see if it shows 1Gbps, i.e. right click the active network adapter and see if it show the connection as 100/Mbps or 1000/Mbps.

P.S. Don't forget that router>to>PC connection, as well as Switch>to>Switch should be done with a cross-over cable.