We removed the internal card and slid in a PC-Card or express card. Now I hear some squawk and squeal over that but I'm sharing the solution I've used dozens of times last year. It's cheap and gets it working.
http://www.geeks.com/details.asp?invtid=WPN511NAR while out of stock is what I used last time.
http://support.dell.com/support/edocs/systems/ins1521/en/om_en/pdf/RT722A02MR.pdf shows this model uses the newer express card.
I can't find a cheap Express card that shows 7 support so try http://www.airlink101.com/products/awll6075.php which is less than 20 at http://www.geeks.com/details.asp?invtid=AWLL6075&cat=NET
As to the Vista install, you may have forget the Dell QuickSet utility. Tell me you installed that on Vista and 7.
Bob
I have a Dell Inspiron 1521 with Windows 7 running after an upgrade also of 1 1G DDR2 RAM and am having sporadic connection to Internet via my Linksys WRT160N wireless router on my ADSL2+ service.
The wireless card on the machine's the Dell Mini WLAN 1390 card and it appears and disappears taking my wireless connection with it.
I have been having this problem since September 2009 and thought that I should do a re-install of Vista then but that doesn't work.
I'm at my wit's end as to what to do as updating the card drivers don't work as the card's not found on the system when I do that.
Please advise as I just don't know what to do again...
Thanks
Gregory

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