Looks to me like the forum is being invaded by bots. I've seen a lot of suspicious new usernames, for example:
Yeah maybe these are real people, but color me skeptical. I noticed three of these joining in a short space of time yesterday right around the same time the page loads started slowing down and failing. Could be coincidence, but I got the sense yesterday that you might be under a DoS attack.
Get yourself right; the world has enough problems.