Excessive collisions at 100BaseT

Have a small home fast ethernet network running peer to peer quite
successfully with three Windows XP machines. Typical transfer speeds
clocked using the Windows Task Manager shows anything up to 45% (i.e. 45
Mbps) but typically around 15-20% utilization for sustained large file
transfers.

However, I've recently added a Win98 machine to the network and have noticed
a dramatic impact on performance. If I leave the Win98 machine with an
autosense config on the NIC (intel 10/100 pci) it negotiates a 100Mbit
connection, but the hub immediately registers constant collisions and any
other network traffic slows to a crawl (e.g. file transfer between two XP
machines drops to around 0.5% - i.e. 500kbps).

If I force the NIC on the Win98 machine to 10BaseT, however, the rest of the
network seems to behave reasonably well, although not quite as quick as it
was previously. When the Win98 machine is switched off, I get back to
roughly the network performance I had before.

Is this the sign of a faulty ethernet adapter on the Win98 machine? Am I
missing a trick on the Win98 configuration?

Any help greatly appreciated, as I'd like to get the Win98 on to the network
at ful speed.

Cheers
Richard




Richard Broughton

In article <2rCDc.77$%c3.21@newsfe5-win>, "Richard Broughton"
<(E-Mail Removed)> wrote:
>Have a small home fast ethernet network running peer to peer quite
>successfully with three Windows XP machines. Typical transfer speeds
>clocked using the Windows Task Manager shows anything up to 45% (i.e. 45
>Mbps) but typically around 15-20% utilization for sustained large file
>transfers.
>
>However, I've recently added a Win98 machine to the network and have noticed
>a dramatic impact on performance. If I leave the Win98 machine with an
>autosense config on the NIC (intel 10/100 pci) it negotiates a 100Mbit
>connection, but the hub immediately registers constant collisions and any
>other network traffic slows to a crawl (e.g. file transfer between two XP
>machines drops to around 0.5% - i.e. 500kbps).
>
>If I force the NIC on the Win98 machine to 10BaseT, however, the rest of the
>network seems to behave reasonably well, although not quite as quick as it
>was previously. When the Win98 machine is switched off, I get back to
>roughly the network performance I had before.
>
>Is this the sign of a faulty ethernet adapter on the Win98 machine? Am I
>missing a trick on the Win98 configuration?
>
>Any help greatly appreciated, as I'd like to get the Win98 on to the network
>at ful speed.
>
>Cheers
>Richard

If you have a hub, not a switch, the problem could be that the NIC on
the Win98 machine has configured itself for full duplex. Hubs don't
support full duplex, and it will cause collisions and slow network
functioning. If that's the case, manually configure the NIC for half
duplex.
--
Best Wishes,
Steve Winograd, MS-MVP (Windows Networking)

Please post any reply as a follow-up message in the news group
for everyone to see. I'm sorry, but I don't answer questions
addressed directly to me in E-mail or news groups.

Microsoft Most Valuable Professional - Windows Networking
http://mvp.support.microsoft.com

Steve Winograd's Networking FAQ
http://www.bcmaven.com/networking/faq.htm

Thanks for the tip - unfortunately it didn't help.

Along the way, however, I did discover that I had the wrong drivers for the
NIC turns out it was an Adaptec card rather than an Intel card, although the
plug'n'play continues to default to recgonising it as intel. Anyway, I
have now replaced the drivers with the correct ones from Adaptec, but still
no joy.

The networking is fine if I select 10 Mbps Full-Duplex or 10 Mbps
Half-Duplex, but fails when I try Auto detect, 100 Mbps Full Duplex or 100
Mbps Half duplex., as before.

I've also tried running the adaptect NIC diagnostic utility from DOS - and
the "local" tests seem fine at both speeds. although there are a few signal
errors at the higher speed on the transmitter test but nothing excessive.

Looks like I'm going to be stuck running at the lower speed for that PC

"Steve Winograd [MVP]" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> In article <2rCDc.77$%c3.21@newsfe5-win>, "Richard Broughton"
> <(E-Mail Removed)> wrote:
> >Have a small home fast ethernet network running peer to peer quite
> >successfully with three Windows XP machines. Typical transfer speeds
> >clocked using the Windows Task Manager shows anything up to 45% (i.e. 45
> >Mbps) but typically around 15-20% utilization for sustained large file
> >transfers.
> >
> >However, I've recently added a Win98 machine to the network and have
noticed
> >a dramatic impact on performance. If I leave the Win98 machine with an
> >autosense config on the NIC (intel 10/100 pci) it negotiates a 100Mbit
> >connection, but the hub immediately registers constant collisions and any
> >other network traffic slows to a crawl (e.g. file transfer between two XP
> >machines drops to around 0.5% - i.e. 500kbps).
> >
> >If I force the NIC on the Win98 machine to 10BaseT, however, the rest of
the
> >network seems to behave reasonably well, although not quite as quick as
it
> >was previously. When the Win98 machine is switched off, I get back to
> >roughly the network performance I had before.
> >
> >Is this the sign of a faulty ethernet adapter on the Win98 machine? Am I
> >missing a trick on the Win98 configuration?
> >
> >Any help greatly appreciated, as I'd like to get the Win98 on to the
network
> >at ful speed.
> >
> >Cheers
> >Richard
>
> If you have a hub, not a switch, the problem could be that the NIC on
> the Win98 machine has configured itself for full duplex. Hubs don't
> support full duplex, and it will cause collisions and slow network
> functioning. If that's the case, manually configure the NIC for half
> duplex.
> --
> Best Wishes,
> Steve Winograd, MS-MVP (Windows Networking)
>
> Please post any reply as a follow-up message in the news group
> for everyone to see. I'm sorry, but I don't answer questions
> addressed directly to me in E-mail or news groups.
>
> Microsoft Most Valuable Professional - Windows Networking
> http://mvp.support.microsoft.com
>
> Steve Winograd's Networking FAQ
> http://www.bcmaven.com/networking/faq.htm

Looks like I spent a lot of time on my Win98 machine for no good reason . .
..

I tracked the problem down to the hub - took it out of the equation and the
network is now flying - well over 50Mbps on sustained transfers between the
XP machines, which is great and at least twice the speed I have been seeing
recently. Looks like a blown capacitor in the hub, so I'll do a bit of
soldering and see if I can fix it. I guess the performance had degraded over
the last few weeks and I didn't notice it.

Not sure exactly why the problem showed up worse with the Win98 machine
connected though. Until I fix or replace the hub I won't be able to bring
the Win98 machine back into the network (logistics of the cable runs), so I
wait to see if it still exhibits any strange behavious then.


"Steve Winograd [MVP]" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> In article <2rCDc.77$%c3.21@newsfe5-win>, "Richard Broughton"
> <(E-Mail Removed)> wrote:
> >Have a small home fast ethernet network running peer to peer quite
> >successfully with three Windows XP machines. Typical transfer speeds
> >clocked using the Windows Task Manager shows anything up to 45% (i.e. 45
> >Mbps) but typically around 15-20% utilization for sustained large file
> >transfers.
> >
> >However, I've recently added a Win98 machine to the network and have
noticed
> >a dramatic impact on performance. If I leave the Win98 machine with an
> >autosense config on the NIC (intel 10/100 pci) it negotiates a 100Mbit
> >connection, but the hub immediately registers constant collisions and any
> >other network traffic slows to a crawl (e.g. file transfer between two XP
> >machines drops to around 0.5% - i.e. 500kbps).
> >
> >If I force the NIC on the Win98 machine to 10BaseT, however, the rest of
the
> >network seems to behave reasonably well, although not quite as quick as
it
> >was previously. When the Win98 machine is switched off, I get back to
> >roughly the network performance I had before.
> >
> >Is this the sign of a faulty ethernet adapter on the Win98 machine? Am I
> >missing a trick on the Win98 configuration?
> >
> >Any help greatly appreciated, as I'd like to get the Win98 on to the
network
> >at ful speed.
> >
> >Cheers
> >Richard
>
> If you have a hub, not a switch, the problem could be that the NIC on
> the Win98 machine has configured itself for full duplex. Hubs don't
> support full duplex, and it will cause collisions and slow network
> functioning. If that's the case, manually configure the NIC for half
> duplex.
> --
> Best Wishes,
> Steve Winograd, MS-MVP (Windows Networking)
>
> Please post any reply as a follow-up message in the news group
> for everyone to see. I'm sorry, but I don't answer questions
> addressed directly to me in E-mail or news groups.
>
> Microsoft Most Valuable Professional - Windows Networking
> http://mvp.support.microsoft.com
>
> Steve Winograd's Networking FAQ
> http://www.bcmaven.com/networking/faq.htm