I although I do not have experience with dell laptops, I have experience setting up a wireless card on an HP laptop. I also have limited experience with Mandrake (I currently use Arch Linux
The first step is to determine if your wireless card is compatiable with Linux. Google should be your friend. I expect that you will get on the following results:
- Yes - you need a linux driver.
- Somewhat - you need to emulate the driver
- No - try again with another card
If the answer is YES, again use Google to find the driver. Hopefully, you will also find installation directions.
If the answer is SOMEWHAT, you need to use and Windows driver and emulate it. I know for my HP laptop, this was the case and I used ndswrapper. I have also heard of madwifi.
If the answer is NO, I am sorry.
I hope this helps.
By the way, how does your laptop run? I am considering purchasing an E1505. What are the specs for your laptop?