What format is the partition? If it's linux swap filesystem, then sure, you can use it
You'll need to use something like fdisk or mkswap to change the type of partition it is though if it's not a linux swap (use:
/sbin/fdisk -l to find out, as root of course
After you make it a linux swap you'll wanna add it to your fstab, something like:
/dev/hdx swap swap defaults (or sw depending on the documentation you find) 0 0
You'll then need to "swapon" which means just type that into a terminal, again, as root. This turns the swap on. Then enjoy.
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