Peter,
    Have you checked Sony's website for a bios update by chance?  I
worked at a place that was a fan of Dell and the Model D610 laptop had
such an issue.  It would not pickup a wireless signal at times even
with several reboots.  It would appear to be random.  Later on I found
a bios update on Dell's site version A03, I think.  I had to flash the
bios and then load the latest driver they provided for the network
card.  That solved the problem of the disappearing wireless
connection.  The bios update also fixed another issue related to power
management, but I don't know if that was related to the wireless card
or not.

good luck,
Derek Buchanan

On Tue, Jan 3, 2012 at 11:06 PM, Peter Shkabara <[log in to unmask]> wrote:
> My daughter's laptop (a new Sony Vaio Z) is having problems with the
> built-in Intel Centrion N 6230 wireless adaptor. The older Vaio Z that she
> still has works fine, but the new one works fine for a while and then
> becomes VERY slow with speeds of 14kbps or so.
>
>
>
> I am considering getting her a USB network adaptor to circumvent the problem
> and am looking for recommendations for such a device. Obviously, small size
> is helpful. Newegg shows various brands including Intellinet, StarTech,
> Roswill, Asus, and Encore. Problem is that reviews show all to have good and
> bad ratings. Any feedback from the list would be appreciated.
>
>
>
> If by chance anyone has a solution to the Centrino adaptor problems, that
> would obviously be even better. So far I have tried new Intel drivers and
> adjusting the networking settings with no improvement. It may work well for
> several hours, and then drop speed for a long time also. Did try changing
> the router frequency to no avail. Interestingly, the signal strength shows
> as being very strong even when speed is slow. PING times to the router are
> 50 to 1000 ms or even timeout when it goes in the slow mode. The router is a
> D-Link DIR_655 in case that may matter.
>
>
>
> Thank you.
>
>
>
> Peter Shkabara
>
> --------------------------
>
> [log in to unmask]
>
>
>
>
>
>
>                         PCBUILD's List Owners:
>                      Bob Wright<[log in to unmask]>
>                        Mark Rode<[log in to unmask]>

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