Just go for it.
It's up to your computer bios to recognize it. Every Os will read bios first before booting and will use every hardware assign by bios. Your available ram will be used first before swap file is used.No need to worry.
I'm planning on buying some more memory, and have a question about adding it. Do I have to do anything special to get a hdd install of knoppix (debian style) to recognize and use the new ram? And is there any way to verify that it is being used?
Just go for it.
It's up to your computer bios to recognize it. Every Os will read bios first before booting and will use every hardware assign by bios. Your available ram will be used first before swap file is used.No need to worry.

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