Indeed, I would suggest identifying what is first using most of your memory.

Something like a free -m, first off will give the general idea of how much memory you already are working with while doing a top -c and shift + m before evening running the install will see specifically what is eating most of your memory up.

From there you can disable the processes that are eating up most of the memory. If there is a redundant process or something that is spawning more children than normal you can run:

ps aux | awk '{print $1}' | sort | uniq -c | sort -k1 -g

or

ps aux | awk '{print $11}' | sort | uniq -c | sort -k1 -g

If you could shoot me the results, I can take a look for ya, but they're pretty obvious.