I'm not sure how else to describe it. I haven't played for a while now, because the game freezes every 3 seconds or so. My PC is fine (I can play other MMORPGs and watch videos all at once and have no problem) so I imagine it must be a setting or something that is wrong. I don't know what to look for or what I can try. Any advice?
Some people experience this. Most users solve it by running the game without vsync or using fullscreen mode.
Also, if you happen to be using an ATI video card you should make sure that you've updated your drivers from the spring releases. Those releases were known to not perform well with Spiral Knights.