12-14 MBps over gigabit...what am I doing wrong?

Discussion in 'Windows Desktop Systems' started by Petros, Mar 31, 2007.

  1. Petros

    Petros Thief IV

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    I have two Realtek 8169 (gigabit) NICs in my two computers, and just got this router for them. Windows says I have a gigabit connection, but setting both NICs to autonegotiation or setting both to 1000Mbps full-duplex only yields 12-14 MB per second over the network. I'm using brand new cat5e cables (and old ones just to make sure), but it's just not getting the speed it's supposed to get.

    Is there something else I should look for?

    By the way, that's when I'm getting a file from the other computer. When I send the file, I get ~18MBps
     
  2. American Zombie

    American Zombie Moderator Staff Member Political User

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    Windows just reports what your adapter is capable to do not how fast your connection is.

    Mine says 100Mbps but my connection is not that fast.
     
  3. Petros

    Petros Thief IV

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    Oh, I mean over the LAN.
     
  4. LeeJend

    LeeJend Moderator

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    12-14MBps means you are running at 100 mbps.

    The router is 1 gig also so it should all work, especially if all the wiring is Cat 5e. Cat 5 might work but is iff'y.

    So check the settings in the router setup. It may default to 100 or it might not want to auto negotiate with the Realtek cards.

    The other possibility... If your MB/CPU/HD is too slow you might not be able to push that much data in and out of the PCs that fast.

    Also, to get the router out of the loop wire the two computer NICs directly using a cross over cable.

    With the crossover only connected see if the NIC card light for 1 gig is on or if the 100 mbps light is on. Check the same with only the router installed.
    -If the 1 gig light is on with cross over and off with router the problem is likely in the router setup or compatibility.
    -If the gig light is on and speed is only 12-14 MBps then I suspect one or both of the computers is speed limited before the NIC.
    -If the gig light is off with both I'm stumped.
     
    Last edited: Mar 31, 2007
    Petros likes this.
  5. Petros

    Petros Thief IV

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    Ok, my NIC apparently didn't update or something. The 100Mbit light was lit. After I unplugged it and popped it back in, everything was as it should be. Thanks, LeeJend!
     
  6. LordOfLA

    LordOfLA Godlike!

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    You'll be limited by your HDD though :) Most you'll get is 55MB/sec your HDD can't write at the 120MB/sec gigabit will give you.
     
  7. Petros

    Petros Thief IV

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    Ah yeah...As long as I can get close to max, I'm happy ;) This router is nice, too, and I've never seen such a slick settings
    interface.
     
  8. ming

    ming OSNN Advanced

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    I would have thought that you'd require Cat6 cables for gigabit, rather than Cat5e. Maybe I missed something when I was reading up on the differences.

    Even so, you should still get a 100mbps connection.
     
  9. LordOfLA

    LordOfLA Godlike!

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    Cat5e was made for gigabit. cat6 just adds extra insulation for better signal quality.
     
  10. _kC_

    _kC_ Moderator

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    max i ever see over my 1gb link is 29-32mbps
    netgear ga311 adapters
    netgear gs605 switch
    netgear dg834g router
    cat5e cables
     
  11. _kC_

    _kC_ Moderator

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    oh and forgot to say.. checkif your cards support jumbo frames.. if they do enable on both cards identical settings.. seems to keep cpu use down while transferring
     
  12. LordOfLA

    LordOfLA Godlike!

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    what is your HDD's sustained write speed? gigabit ethernet is limited by that and bus capacity.
     
  13. Geffy

    Geffy Moderator Folding Team

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    what if you are writing to the pipe from memory :p
     
  14. LordOfLA

    LordOfLA Godlike!

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    than I'd be suprised if you couldn't saturate 10gE :D
     
  15. Cilix

    Cilix OSNN Junior Addict

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    Unless your using fiber optics, you wont acheive a true Gigabit speed unfortunately. Also, you should leave it set to force 100 Full Duplex to settle any autonegotiation issues. Cat6 cables could also help as well, as they are gold fitted and better protected so there is less chance for crosstalk and EMI to degrade the signal strength.
     
  16. LordOfLA

    LordOfLA Godlike!

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    you will get gigabit over copper. We get gigabit over ethernet at work.

    Someone talking out the wrong hole :D
     
  17. Cilix

    Cilix OSNN Junior Addict

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    Theotically, yes you can. Practically, nah you cant. Theres too many factors involved.

    The practically obsolete standard of 1000BASE-CX has been replaced with the single and multi mode fiber standards of 1000BASE-LX and 1000BASE-SX. Hell, even gigabit ethernet has been replaced with 10GbE. I wish i had one of those lines sitting on the pole outside my house :D
     
  18. LordOfLA

    LordOfLA Godlike!

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    I work at a datacentre where we use 1000baseT, 1000base-LX and 1000base-SX 24/7. The later of which operate via CWDM muliplexers to our uplink carriers.

    Our switches are able to sustain 100MB/sec over gigabit uplinks. Those with dual uplinks are happy at 190-200MB/sec.

    The limiting factor for domestic use as I said is disk read/write perfomance and total I/O system capacity.