Question : Slow Network Connections to 100Mbps Clients

I'm experiencing extremely slow speeds with network file transfers between my brand new Dell server and my couple year old Compaq notebooks.  Recently I've moved my notebook users onto ethernet connections (1000mbps) from the office WiFi connection (54G) but this has resulted in their speeds slowing to a crawl.  I've tried different ports, different cables, and different patch panel and switch ports to check for network infrastructure issues, but everything is still slow.  When I bring up the Windows XP task manager the networking graph shows 0.25% - 1% network utilization.  That can't be right can it?

Here's what I have in the way of hardware and how it's all connected....
Dell PowerEdge 2900 Win2k3 SBS box w/3x300Gb SAS 10krpm drives (RAID5), integrated 1Gbps ethernet
Dell Powerconnect 2724 24 port Gigabit switch (currently in unmanaged mode)
Dell Powerconnect 2324 24 port 10/100 switch (unmanaged, daisy-chained to other switch via 1 of 2 gigabit "server" ports on the switch)
Dell workstations (various speeds, all Gigabit capable P4's)
Compaq Presario V2000 notebooks (various speeds, all Centrino, all 10/100, B/G capable)
Linksys WAP54GAP 54G access port (cabled to 10/100 switch)
Symantec Router (can't remember exact model, it's 300 something, SPI VPN firewall variety)
CAT5E wiring throughout office into 3 12 port CAT5E patch panels then into network switches.


So long story short, the network seems to be slow as molasses in January.  For whatever reason file transfers over the WiFi seem to be faster than wired for the notebooks.  I haven't done a formal test yet but the notebook WiFi transfers seem about as fast as the Dell workstation gigabit transfers, or just a tad slower.  I'm testing the speeds using a 1GB windows folder that includes 1x 400mb zip file and the rest in smaller install files.

Any ideas?

Answer : Slow Network Connections to 100Mbps Clients

THE SOLUTION!

on the server, go to a command prompt and type in:

netsh int ip set chimney DISABLED
and press enter

This disables the Microsoft Chimney Drivers which are used for the TCP IP Offloading Engine which is available on the Broadcom NIC that ships on the Motherboard of the Dell PE 2900 Server.

ALL DELL PowerEdge 2900 Servers which use BROADCOM NICs have a ToE problem whereby ToE causes older style NIC cards or other non-broadcom NICs to perform really poorly when interacting with the server.

Disabling ToE and the Microsoft Chimney Drivers using the command i provided above instantly solves the performance problem and allows you to restore the server and any workstations back to Auto-Negotiate.  One more note, ive found that disabling FLOW CONTROL is also very useful as some older devices do not support this.

We have a full blog posting on our blog website which is: http://mbccs.blogspot.com/