Poor wireless connection under Gentoo (ndiswrapper)

[micromoog]

I'm getting poor wireless performance under Gentoo. I can place the
machine in a particular spot in my house (fairly far from the access
point), boot into Windows XP, and get a 54Mbps connection with no
problems. If I don't physically move the machine at all and boot into
Gentoo, I get 24Mbps with bad lag (in an ssh session, it'll stop
responding about every 5-10 seconds for about 1-2 seconds. Painful for
shell sessions).

It's a Dell D610 with the Broadcom 4309 built-in wireless adapter. I'm
using ndiswrapper 1.1-r1 with the R74092us.EXE driver. My commands to
bring up the interface are simple enough:

/sbin/modprobe ndiswrapper
/usr/sbin/iwconfig wlan0 essid 1x43y54g99
/sbin/dhcpcd wlan0

Under both Windows and Gentoo, the signal strength is reported as
around -75db at this location, so it's not very strong. If I move the
computer closer to the access point so that the signal strength comes
up to -50db or so, it works great. I just don't understand why the
Gentoo setup doesn't handle a weak signal as well as the Windows setup.
I'd like to avoid reconfiguring my network's physical layout, since I
know the computer's hardware is capable of operating well under these
conditions.

Does anyone have any similar experiences/advice?

[Paul Bredbury]

Post by micromoog
It's a Dell D610 with the Broadcom 4309 built-in wireless adapter. I'm
using ndiswrapper 1.1-r1 with the R74092us.EXE driver. My commands to
/sbin/modprobe ndiswrapper
/usr/sbin/iwconfig wlan0 essid 1x43y54g99
/sbin/dhcpcd wlan0

I have a Dell Inspiron 5160 with the same network card and same version
of ndiswrapper, running reliably at 54 Mb/s. To install it, I ran:

ndiswrapper -i bcmwl5a.inf

In /etc/ndiswrapper/bcmwl5a, I have:

-rw-r--r-- 1 root root 542 May 9 23:25 14E4:4318.5.conf
-rw-r--r-- 1 root root 540 May 9 23:25 14E4:4318:1028:0005.5.conf
-rw-r--r-- 1 root root 534 May 9 23:25 14E4:4318:1028:0006.5.conf
-rw-r--r-- 1 root root 608 May 9 23:25 14E4:4319.5.conf
-rw-r--r-- 1 root root 606 May 9 23:25 14E4:4319:1028:0005.5.conf
-rw-r--r-- 1 root root 600 May 9 23:25 14E4:4319:1028:0006.5.conf
-rw-r--r-- 1 root root 542 May 9 23:25 14E4:4320.5.conf
-rw-r--r-- 1 root root 542 May 9 23:25 14E4:4320:1028:0001.5.conf
-rw-r--r-- 1 root root 536 May 9 23:25 14E4:4320:1028:0002.5.conf
-rw-r--r-- 1 root root 540 May 9 23:25 14E4:4320:1028:0003.5.conf
-rw-r--r-- 1 root root 534 May 9 23:25 14E4:4320:1028:0004.5.conf
-rw-r--r-- 1 root root 608 May 9 23:25 14E4:4324.5.conf
-rw-r--r-- 1 root root 608 May 9 23:25 14E4:4324:1028:0001.5.conf
-rw-r--r-- 1 root root 602 May 9 23:25 14E4:4324:1028:0002.5.conf
-rw-r--r-- 1 root root 606 May 9 23:25 14E4:4324:1028:0003.5.conf
-rw-r--r-- 1 root root 600 May 9 23:25 14E4:4324:1028:0004.5.conf
-rw-r--r-- 1 root root 369024 May 9 23:25 bcmwl5.sys
-rw-r--r-- 1 root root 25674 May 9 23:25 bcmwl5a.inf

I'm not sure if that's the same driver that you're using.

Can't you use iwconfig to change the speed? E.g.:
iwconfig wlan0 rate 54M

[Paul Bredbury]

Post by Paul Bredbury

Post by micromoog
It's a Dell D610 with the Broadcom 4309 built-in wireless adapter. I'm
using ndiswrapper 1.1-r1 with the R74092us.EXE driver. My commands to

I'm not sure if that's the same driver that you're using.

There are different driver versions between UK and US - I'm using the UK
version.

For the US version, I think you want the R94827.EXE driver from
http://www.dell.com/ - it was released in March 2005, with the note:
"This release corrects a performance related issue on channels 3 thru 9
with the Dell Wireless 1450 Dual Band Mini PCI network adapter."

The "Dell Wireless 1450" is the Broadcom 4309.

Wine can be used to run the executable, to extract its files.

[micromoog]

Post by Paul Bredbury

Post by Paul Bredbury

Post by micromoog
It's a Dell D610 with the Broadcom 4309 built-in wireless adapter. I'm
using ndiswrapper 1.1-r1 with the R74092us.EXE driver. My commands to

I'm not sure if that's the same driver that you're using.

There are different driver versions between UK and US - I'm using the UK
version.
For the US version, I think you want the R94827.EXE driver from
"This release corrects a performance related issue on channels 3 thru 9
with the Dell Wireless 1450 Dual Band Mini PCI network adapter."
The "Dell Wireless 1450" is the Broadcom 4309.
Wine can be used to run the executable, toextract its files.

I installed that newer driver, and it did indeed improve the
performance. Apparently they tweaked something in the way it handles
weak signals (and not just for channels 3-9, either). Thanks a lot for
the suggestion!