So I have been having this issue as long as I have been raiding, and I cannot seem to rectify it; every 30 seconds or so the game will start to stutter, the sound not so much affected but the graphics and gameplay seem to freeze intermittently, as if having a sudden drop in frame rate.. it persists for five-seven seconds and resolves itself, but it can be very debilitating as the game seems to run sluggishly for the duration.
It happens with every raid I do, regardless of logging off/in, how long I've been playing, or how low I set my graphics settings. Battle effects for everyone but myself is turned off, things are set to an absolute minimum but I cannot seem to get rid of the stutter.
EDIT: I think it is also important to note that, yes, my graphics drivers are updated and I am not running any secondary programs in the background whilst playing- that also means no antivirus or anything.
Specs:
Win7 (64-bit)
AMD Phenom II X4 965 Processor (Quad Core, ~3.4 Ghz)
8 GB RAM
GeForce GTX 460 Graphics Card 1 GB DDR5