The software will use as much memory as it needs(for it to reserve memory, the software would need to be designed that way). As long as you keep enough free memory, that should not be an issue.
One thing that helps is to save to a dedicated HDD/SDD since latency on hard drives can cause frame skips if the drive is doing other things(running programs/windows).
ok, so when im recording i shouldnt have any other programs running. The problem is that im on my old pc and building another with multiple HDDs and SSD, 16GB of ram. I have a WD my passport which i backup to. Should i partition that and send my recordings to that?
Is your recording software or hardware based? Hardware based tends to work even with the system being used for other things. sometimes software needs more free system resources since the cpu is doing all the work.
A dedicated drive has to be just a drive, not a partition on a drive(if nothing else is using the drive, it should be ok to use the existing partition).
If the drive is external, you may also run into some problems of bandwidth limits(depending on the video bit rate.).