Does the ethernet adapter on a P5P800 work at 1000baseT?

  • Thread starter Thread starter jean
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J

jean

I just purchased a gigabit switch (D-Link DGS-1005D) to upgrade my network
from 100baseT to gigabit. I changed the network card on my Linux box and it
booted up, configured the card and I saw the light on my switch indicating a
link at gigabit speed.

On my PC running Windows 2000, after rebooting, just to make sure, the speed
is still 100Mbits. I tried to tweak all the parameters to their maximum
settings but it still shows 100Mbits. In the selection box for media
selection, I have it set on auto, but there is no setting to force it to
either half or full duplex gigabit, only lower speeds (100Mbits and lower).

I have version 7.21.1.3 of the Marvel driver.

I did not change the network cables because I was told that cat 5 is OK for
gigabit networks, especially for the short distances I have at home (15
feet).

Anyone have any ideas?

Jean
 
"jean" said:
I just purchased a gigabit switch (D-Link DGS-1005D) to upgrade my network
from 100baseT to gigabit. I changed the network card on my Linux box and it
booted up, configured the card and I saw the light on my switch indicating a
link at gigabit speed.

On my PC running Windows 2000, after rebooting, just to make sure, the speed
is still 100Mbits. I tried to tweak all the parameters to their maximum
settings but it still shows 100Mbits. In the selection box for media
selection, I have it set on auto, but there is no setting to force it to
either half or full duplex gigabit, only lower speeds (100Mbits and lower).

I have version 7.21.1.3 of the Marvel driver.

I did not change the network cables because I was told that cat 5 is OK for
gigabit networks, especially for the short distances I have at home (15
feet).

Anyone have any ideas?

Jean
Click to expand...

Are there eight wires in the cable, and are they all connected ?

A four wire cable, with eight pin connectors on either end, is
good for 10/100BT but not gigabit. Gigabit needs all eight wires.

You can use the Marvell Yukon Virtual Cable Tester (VCT) to
see if all eight wires are making contact with the other
device. Background info about VCT is here (VCT uses TDR and
analyses reflections from the cable, to determine if the cable
is open, shorted, or correctly connected). It should also be
in your manual.

http://marvell.com/products/transceivers/singleport/VCT_White_Paper.pdf

When I had a failure like this, the Ethernet connector turned out
to be dirty. One of the eight wires was not making contact. Repeated
insertion and removal of the cable eventually got it working.

It is probably best to power off the router while using VCT. That
prevents any packets or pulses sent by the router from confusing
VCT.

Gigabit can also work with a crossover cable, as well as a normal
cable. GbE can figure out how the wires are connected, and correct
polarity errors, or if the cable is crossover, it can still work.
(I think I saw the polarity correction feature in a datasheet for
a chip.)

HTH,
Paul
 
Paul said:
Are there eight wires in the cable, and are they all connected ?

A four wire cable, with eight pin connectors on either end, is
good for 10/100BT but not gigabit. Gigabit needs all eight wires.
Click to expand...

Thanks for your reply

I changed the cable for a different one and now it shows a gigabit
connection rate (yeah). The only thing I am still not sure of, is the speed
it is running at for transfers to another PC. My Linux box is connected to
the switch and shows a gigabit connection but the transfer from my W2K PC is
not any faster. I just tried to transfer over 800Mb (actual 44,849,152
bytes ) and it took 145.22 seconds. I don't think my math is off but that
gives me a bit over 46Mbits / sec (844,849,152 bytes * 8 / 145.22 =
46,541,752 bits / sec) which is in 100baseT territory. I know I still have
a load of stuff to do on my linux box and I still have many tests to do with
parameters. Right now, I have the MTU set to 1500, should it be set to
9014? I am not very sure how it is set in Linux or if it needs to be
cahnged to get better performance, at any rate, my linux box was not very
busy when doing the transfers (using Samba BTW), only reaching 30% busy once
in a while.

Jean
 
Jean,
It doesn't matter how fast your network is.
Your speed is limited by your harddrives sustained transfer rate.
46 Mbits is good for a one disk system. 100 Mbits is burst mode for a 100ATA
drive.
150 or 300 Mbits for SATA in burst mode.

An 8 disk RAID or RAM transfer is a different story.
 
John, you could be right, but 46Mbits is 5.75 Mbytes sustained transfer
rate, which seems kinda slow for the system and drives I have. I am going
from SATA drives in a RAID 1 config (on a 3Ghz P4 running W2K) to a Linux
system (1.4Ghz Athlon) with 2 80Gb IDE drives in a RAID 1 config. Granted
there are a lot of layers of software and hardware but I would have expected
a bit better performance. I am trying to find a network testing tool I can
use that goes across OSes (Windows and Linux).

Jean
 
I found something called Qcheck by Ixia (http://www.ixiacom.com/ freeware
BTW) and they have what is called an endpoint for many platforms and OSes
including many flavors of Linux. I was able to test my connection from my
W2K PC to my Linux PC. I got 421Mbps between the two which is in keeping
with gigabit speeds. Now I will try to tweak the parameters to see if that
figure can be improved.

Thanks everyone for replying.

Jean
 
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