You can't add 32gb, the max supported capacity for that motherboard is already 32gb.
It is unlikely that spending money on an old FX system is a good idea.
Right now it is at 0gb. The old memory went bad earlier this year. Originally I was running 16gb but since I have to replace the memory I figured I'd go all the way to 32gb As far as spending money on it not being a good idea, I don't see why, it worked splendidly until this happened.
If you go to a ram vendor web site, you can access their ram selection app.
Most ram vendors have them.
Enter your motherboard and you will get a list of supported ram kits.
As to spending on a FX system, I suppose you could.
But, you will be buying ddr3 ram which is no longer used in current gen processors.
The FX cores are relatively slow, at least for a gamer.
If you are running batch apps, a FX-9590 with 8 threads, that is a much better case.