Another network issue..1 pc at 1 gigabit, other at 100megabits..why?

Caporegime
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Hi

Back again with another network issue.

I have 3 PCs connected to a gigabit switch via cat5e (home made) ethernet cables

HTPC, DESKTOP, SERVER

the HTPC and SERVER can send/receive at gigabit speeds (90MB)
the DESKTOP and SERVER only communicate at 100mbits

the issue cannot be with the server or switch.

the issue must be with the desktop onboard NIC/drivers/something
or is it possible that a network cable if not terminated properly would only provide 10/100 speeds? (i do not know if this is possible).

according to the mobo specs the asus P6T SE is gigabit capable
 
or is it possible that a network cable if not terminated properly would only provide 10/100 speeds? (i do not know if this is possible).

Possible. There are four pairs in a network cable. 10/100 only needs two of them, Gigabit needs all four. (There are some really cheap cables that only have two pairs in them. Often supplied with cheap routers that are only 10/100 capable).

The Windows task manager will tell you what speed each machine has sync'd at. Find out which one is slow and then swap the cables around. Does the problem follow the cable?
 
i tested the cable when i terminated it.. all 8 lights illuminated. maybe one has come loose.

reporting 100 in task manager

cable tester still reports all 8 connections
 
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Well you need to eliminate it by making some changes. Swap the cable from the server to the desktop and see if it follows the cable.
 
Can you manually set the NIC to Gigabit full duplex via the properties? Sometime they don't autodetect the speed correctly
 
100% not the cable. just swapped it (end in htpc to the desktop) and back again
1gigabit in htpc and 100megabit in desktop. problem lies in the NIC/drivers
 
Cable CAT makes no difference to reported speed. 8 cores = 1Gbps, 4 cores = 100Mbps. Simple as that.

What? How many network cables do you see with 4 wires attached? (ignoring telephone cables) Both ends are terminated with 8 wires

A CAT5 cable with 8 cables attached at either won't report to be connected at gigabit speed
 
What? How many network cables do you see with 4 wires attached? (ignoring telephone cables) Both ends are terminated with 8 wires

A CAT5 cable with 8 cables attached at either won't report to be connected at gigabit speed

Yes it will..
 
I have to reinstall windows this weekend so if it is not working by then i will just buy a pci-e gigabit one i guess.
 
What? How many network cables do you see with 4 wires attached? (ignoring telephone cables) Both ends are terminated with 8 wires

Rare, but they do exist. I received one with the free router Plusnet sent to me last week (and I do know the difference between a network cable and a telephone cable). This isn't the first network cable I've seen that's like this.

It's more likely that you'd have all four pairs there, but not terminated correctly. You can end up with a cable that'll work fine for 10/100 but won't for Gigabit.


A CAT5 cable with 8 cables attached at either won't report to be connected at gigabit speed

It will. Over reasonably short distances they'll usually work a Gigabit speeds as well. I've found Cat5 network cables installed that have been working just fine at Gigabit speeds for years.

@al4x What motherboard is in the machine with the problem?
 
@al4x What motherboard is in the machine with the problem?

It's an Asus p6t se.. Pretty poor 1366 socket board.

Oh, thought I mentioned its definitely cat 5e.it took me a long time to find a retailer that could conform it was cat5e!
 
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You definitely running the correct drivers for the NIC? Grab it from the ASUS site and give that a shot.

Unplug, nuke your network connections, update driver and try from scratch.
 
Have you checked that the network socket on the motherboard looks okay? Nothing bent or missing?

It's very unlikely of course.

i will check later. its a odd one this as the problem is port/driver or something i cant even think of

even tried another device.. still 100mbps
 
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