100Mbit PCcard only running at 10Mbits, help!

Discussion in 'Windows Networking' started by Dave Williams, Nov 30, 2003.

  1. Hi everyone

    I have a 100Mbit PCMCIA NIC in my laptop which will only run at 10%
    capacity even though the PC at the other end is definitely 100Mbit and
    has run at 100Mbit in the past. The PCMCIA bus is a Texas Instruments
    PCI-1225 CardBus Controller which according to the TI website has:
    'Pipelined Architecture Allows Greater Than 130-MBps Throughput From
    CardBus-to-PCI and From PCI-to-CardBus' (see

    Does this mean its 130MBps full duplex or only one way thus preventing a
    true 100Mbit connection?

    Both systems WinXP Pro, a P3 600 384MB RAM and XP 2600+ 256MB RAM, both
    show 100Mbps connection in the network interface properties, connection
    type, autosense (only option that provides 100Mbps, the others provide
    only 100Kbps) manufacturer: sitecom.

    Thanks for your help
    Dave Williams, Nov 30, 2003
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  2. Dave Williams

    daytripper Guest

    It appears you are saying both cards actually indicate they are operating
    their media connections at 100mbps/full duplex, therefore the conclusion I
    draw is you are complaining about throughput. Correct?

    Specsmanship: the claim is most likely the theoretical peak throughput in one
    direction (obviously if you're going for "peak" you can't be switching from
    reads to writes and back). What does that mean? Well, electronically, they can
    wiggle the wires at 33mhz.

    That doesn't mean your network adapter can use all or even most of that peak
    throughput to do actual work. Efficiency of the nic and its driver alike
    verses transaction overhead will dictate how fast your network adapter can
    move real data...

    daytripper, Nov 30, 2003
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  3. Well, I have a netgear fw/router box (FR314) connecting 2 Windows 2000 Pro
    machines together, I get approx 50Mbit/s everytime I transfer a large enough
    file (disk sharing) ... both pc's have 100Mbit nic's.

    You ort to be getting more than 10Mbit I should think - assuming both pc's can
    cope with the speed you want (50Mbit/s = a tad over 6MByte/s).

    Saying that, I can only ever get 10Mbit from my laptop (pcmcia card bus card),
    even if I set the laptops nic to 100Mbit full-dup ... it seems to have a problem
    with my netgear router, the laptop card won't see the routers 100Mbit lan ports
    as 100Mbit, it only wants to see them as 10Mbit :( ... connecting a simple hub
    between the laptop and the router box fixes this though - the laptop nic then
    see's the lan as 100Mbit.

    wot.email.addr, Dec 1, 2003
  4. Does your laptop manage more than 10Mbps when its running through the
    hub and showing 100Mbps?

    On the task manager networking graph both my machines claim 100Mbit
    connections but when copying a big file from the laptop to the tabletop
    PC (or visa versa, directly through a twisted pair (?) cable) the max.
    data throughput is a touch under 10% and never peaks over this. As
    there's no hub or router and both cards claim 100Mbit and the cardbus
    claims 130Mbit peak it must be drivers or someone isn't telling the
    whole truth about their specs. Even the drivers are claiming 100Mbit

    Daytripper mentions 'Efficiency of the nic and its driver alike verses
    transaction overhead will dictate how fast your network adapter can move
    real data... '. If that's the way things are then I could go out and buy
    a gigabit nic only to find it's a little 'inefficient' and can only
    manage 5Mbits. That certainly wouldn't make a satisfied customer. I
    could accept that maybe my PCMCIA nic can only peak at 100Mbps and
    averages less but because it never gets over 10Mbps I'm thinking there
    must be a solvable problem here . . . . but I'm stuck. I'm aiming for at
    least 5MB/sec for a VST networking program so anything under and the
    100Mbps nic I bought is a waste of money. I already have a 10Mbit card
    that can manage 10Mbps (!).

    Any ideas? Thanks for your time.
    Dave Williams, Dec 1, 2003
  5. Dave Williams

    daytripper Guest

    And yet, that IS the way things are.

    Go stick your gigabit card in a conventional 33mhz/32b peecee PCI bus and see
    if you ever hit anything remotely close to a cooked gig.

    Yet, the card fits the slot - surely something must be wrong?
    Well, no. That's the way it is.

    You wouldn't be the first person to notice his "100mbit" lan running at
    significantly lower than peak throughput. If the nic uses host resources to
    move data instead of an embedded engine, and your system can't chug through
    the driver code fast enough to keep the phy fed, you get what you get...

    Finally, just because there's always the possibility of excessive error rates,
    have you tried a different cable yet?

    /daytripper (Otherwise, that's the way it is ;-)
    daytripper, Dec 2, 2003
  6. Dave,

    You mentioned that your laptop has a CardBus controller. But I
    could not help notice you did not state whether your NIC is a
    32-bit CardBus or 16-bit PC Card.

    16-bit PC Cards are roughly equivalent to legacy 16-bit ISA
    cards with a theoretical maximum throughput of 10~20Mbps. That
    may help explain your situation.
    Michael J. Apollyon, Dec 2, 2003
  7. According to the manufacturer's website it is 32-bit, capable of 130Mbit
    peak flow, hence the 10Mbit limitation is puzzling me . . .
    Dave Williams, Dec 2, 2003
  8. I understand the possibility of bus limitations but the specs of this
    bus are 130Mbit. I don't know hardware in much detail and I understand
    the quoted 130Mbits may be in a different context to actual data
    throughput so I've quoted some of the specs below to see if you may be
    able to shed some light on it. My 10Mbps is so much less than the quoted
    130Mbps I am assuming the bus isn't the bottle neck. Here are some of
    the specs, the last one being the one I've been referring to:

    -PCI Bus Power Management Interface Specification 1.0 Compliant
    ACPI 1.0 Compliant
    -Fully Compatible With the Intelâ„¢ 430TX (Mobile Triton II) Chipset
    -Packaged in a 208-Pin Low-Profile QFP (PDV) or GHK High Density Ball
    Grid Array (BGA)
    -PCI Local Bus Specification Revision 2.2 Compliant
    -1997 PC Card Standard Compliant
    -PC 99 Compliant
    -3.3-V Core Logic With Universal PCI Interfaces Compatible With 3.3-V
    and 5-VPCI Signaling Environments
    -Mix-and-Match 5-V/3.3-V 16-bit PC Cards and 3.3-V CardBus Cards
    -Supports Two PC Card or CardBus Slots With Hot Insertion and Removal
    -Uses Serial Interface to TI TPS2202/2206 Dual-Slot PC Card Power Switch
    -Supports Burst Transfers to Maximize Data Throughput on the PCI Bus and
    CardBus Bus
    -Supports Parallel PCI Interrupts, Parallel ISA IRQ and Parallel PCI
    Interrupts, SerialISA IRQ With Parallel PCI Interrupts, and Serial ISA
    IRQ and PCI Interrupts
    -Serial EEPROM Interface for Loading Subsystem ID and Subsystem Vendor
    -Pipelined Architecture Allows Greater Than 130-MBps Throughput From
    CardBus-to-PCI and From PCI-to-CardBus

    Thanks for your input!

    I'm yet to try another cable . . .
    Dave Williams, Dec 3, 2003
  9. Apologies! It is only 16-bit but does claim 130Mbit CardBus-to-PCI data
    throughput. I've quoted some of the specs the other thread. I suppose
    the bottle neck could be else where, like the 16-bit part of the
    CardBus, but wouldn't that make the 130Mbit CardBus-to-PCI capability
    Dave Williams, Dec 3, 2003
  10. You mentioned that your laptop has a CardBus controller. But I
    The source of your bottleneck is not the laptop's CardBus controller, it
    is your 16-bit PC Card Network Adapter. Replace it with a 32-bit
    CardBus unit and you will achieve near 100Mbps network speeds.

    Fast Ethernet 16-bit PC Cards (and older ISA cards) were once common.
    They would get you on a 100Mbps network, but don't expect them to
    perform ANYWHERE near that speed. (I still have an Argosy EN200 10/100
    PCMCIA card in my old ThinkPad 760C.)

    32-bit CardBus cards can be distinguished from their lowly 16-bit
    siblings by a brass or gold grounding strip at the connector end.
    Michael J. Apollyon, Dec 3, 2003
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