Adding Ram to my Laptop

I am about to add ram to my laptop. My laptop currently has 512 and i recently purchased a 1 gig kingston chip.

Before i install i wanted to double check a few things.

first, i read that it is not allowed to install two different sized memory chips in a dual channel. I beleive i have a dual channel, but i will know for sure in the morning when i open the laptop up.

if i do remove the memory chips, does it matter that i am replacing 2 memory chips with just 1?

I read this from the dell website "NOTE: To get maximum performance/dual-channel memory bandwidth capability, both memory module connectors must contain memory modules and the modules must be of the same size and configuration."

Does this mean that i should have gotten 2 1 gig ram or does this mean that if i install a 1 gig alone that it won't be as efficient.

Also, if i remove my old ram chips would that effect the information that is currently on my computer?

Thanks for the help, just want to make sure i do the right thing before i screw with my laptop!

 

To run memory in dual channel, you have to have equal amounts of compatitable memory in each memory memory channel.

If you notebook has 512mb total and is running in dual channel it will have two sticks of 256mb
Note! You dont have to run your memory in dual channel & if you dont have equal memory in each channel it wont, but if your memory is compatitable your notebook will still operate
There is no setting for Dual channel mode it's automatic.

Dells web site should have very good mantainance guides for all thier notebooks

You can run Everest it will tell you how many memory slots your Notebook has & it can tell you how much memory is installed in each.
It will also note if your running in dual channel mode, look in Motherboard/Chipset
Everest:
http://majorgeeks.com/EVEREST_Free_Edition_d4181.html