I recently had issues with the reliability of Broadcom cards and Vigor 2820 wireless adsl routers. Specifically the Broadcom cards were embedded ones in two different HP laptops – a 6715S and a Touchsmart Tx2. Given the difference in the cards I was fairly convinced that the answer lay with the router – but the situation was compounded by the fact that both had bee migrated to Windows 7 from Vista (although different versions).
The main symptoms of the problem would be the very intermittent nature of the connection and the lack of any specific remedy. The driver versions were checked and the router firmware was a relatively recent version. Both the laptops could connect and sustain a wireless nto other older vigor routers at other locations and appeared to have no issues connecting to other access points. Using an external usb netgear wireless card provided flawless connectivity but at the expense of have a dangling network card waiting to get damaged.
On speaking to Seg – Drayteks UK distributor – my contact suggested that we look at the channel settings and the bands that were being used.
At that stage I noted that the drivers for both HPs were substantially different and that they had very few settings in common (at least not that they seemed common). The first point of call was the router settings and switching to Wireless mode 11G only and making sure long preamble was off and that Tx Burst was disabled. In the advanced settings section the operation mode was set to mixed mode and the channel bandwidth to 20/40. The guard interval was auto and the Agreggation MSDU was enabled.
Then on the wireless card side – a Broadcom.11a/b/g – I looked at the range of settings and specifically whether any of them related to channel negotiation or a bias towards older wireless settings such as 11b. Afterburner was disabled and AP compatibility set for Broader Compatibility.Finally the opt for band preference was set to 11g/b and disable bands set to disable 802.11a – the last options being WZC IBSS Channel number – which I set to 40 and Xpress Technology disabled.
The result was a rock solid connection which has behaved flawless. I applied similar changes to the TX2 card and was able get the same result – a working connection with great speed. So it goes to show – compatibility sometimes needs compromise on both sides