No hard feelings
I don't think that something went wrong, it's just that some applications require more resources these days, due to extended business needs, or they simply have memory leaks, even some enterprise products.
But 512 MB ram should be enough, a while ago I had FreeBSD 6.0 with 3Ghz CPU and 512 MB RAM, running AMP + 700 user accounts, each has shell and ftp access with 1G quota, and it was doing pretty good.
But let's not change the subject of the topic - the site performance is much better