I don't want to blame Xenforo, but when the other software was installed, I could have 400 users online at a time and the Server load would stay at <= 0.20, Memory used(usage) at 0.25% and Swap Used at 0.27%-0.30%, max 0.35%
The last time my vps was under such load was when I was running vbseo, which I had to get rid of and I don't want to get rid of xenforo but I will if I have to.
The load has been consistent and since I switched to Xenforo, the highest amount of visitors at one time has been 120-130. So far I have disabled "search" for everyone ... I'm thinking the .htaccess rewrite may have something to do with it.