Well he can't unfortunately since he's running 32-bit
Not to sound harsh, but ZFS isn't going to forgive you for it if your hardware isn't up to spec. It doesn't let you go with less hardware requirements because you are poor, you live in a country where hardware is hard to come by, or you're 'just waiting until the next paycheck'. Either you accept the risk or you don't. Quite frankly(and this is going to sound really mean) I'm somewhat glad 9.2.0 is more strict with the RAM requirements. We're seeing many more people statistically losing their pools from 9.2.0 than from prior versions. Not that it was designed that way, but its flushing out the people that haven't met the minimum requirements for quite a while. Unfortunately, it's also causing a lot of data loss. While I do feel bad for them, I'm not missing any sleep over it since it's been clearly explained in the manual what the minimum requirements for FreeNAS were and people have ignored them. In some cases, for years. Hey, anyone that values their data should have backups for just a scenario like this.
And I know you know better Knowltey, i'm just explaining for the benefit of the OP.