Layback Bear is right, and I sort of mentioned back in 19 that those boxes shouldn't be checked.
And for the record those boot options are mainly for testing/diagnostic purposes. With that box checked all you're basically doing is limiting the processor. And even if it has less cores, you're NOT enhancing anything by checking that box.
I've no idea how this FUD of a tweak is still around but it enhances nothing. You would best be served to uncheck those boxes and leave them alone.
That said that particular box shouldn't have an effect on your memory, thus the problem could be elsewhere. Still I'd uncheck it anyway as it's doing nothing for you.
Your system, your choice.