This tip is designed for increased BROADBAND speed in Windows XP while using standard Network Interface cards (NIC) that are connected to ADSL modems, or when using any directly-connected USB ADSL modem.
To speed up the
Internet connection speed we need to configure a special buffer in the
computer's memory in order to enable it to better deal with interrupts made
from the NIC or the USB modem.
This tip is only
recommended if you have 256MB RAM or higher.
Step #1 - Identify the IRQ used by the NIC/USB modem
Follow these
steps:
1.
Open the System
Information tool by running MSINFO32.EXE from the Run command.
2.
Expand System Summary
> Hardware Resources > IRQs.
3.
Look for the listing
made for your NIC (in my case - a Intel(R) PRO/100+ Management Adapter). Note
the IRQ next to the specified line (in my case - IRQ21).
In case of USB
modems you will first need to find the right USB device used by your modem.
Follow these steps:
1.
Open the Device Manager
tool by running DEVMGMT.MSC from the Run command (or by right-clicking My
Computer > Hardware tab > Device Manager button).
2.
Scroll down to Universal
Serial Bus controllers and expand it.
3.
Right-click the USB Root
Hub and select Properties. Note that you might need to do so for all listed USB
Root hubs (if there are more than one) in order to find the right one.
4.
In the Power tab, look
for your USB ADSL modem.
5.
In the Resources tab
look for the assigned IRQ (in this case - IRQ21).
6.
This is the IRQ we're
looking for.
Lamer note: IRQs and modem names might vary...
Step #2 - Modify the system.ini file
Follow these
steps:
1.
Run SYSEDIT.EXE from the
Run command.
2.
Expand the system.ini
file window.
3.
Scroll down almost to
the end of the file till you find a line called [386enh].
4.
Press Enter to make one
blank line, and in that line type
IrqX=4096
where X is the
designated IRQ number we found in step #1, in my case it's IRQ21.
Note: This line IS CASE SENSITIVE!!!
5.
Click on the File menu,
then choose Save.
6.
Close SYSEDIT and reboot
your computer.
Done. Speed
improvement will be noticed after the computer reboots.
Update: The most speed improvement is visible with USB A/DSL
modems, however there are reports that this tweak also does good for regular
NICs. In any case, it won't harm your system, so why not try it yourself and
let me know what you find.
