FPS issues

[Soldout]

First of all I don't know too much about computers, just putting that out there ahead of time.

I stopped playing WoW for a few months and I've recently started playing again on a new low lvl character. I normally sit right at 70 fps while I'm out doing quests or in any area that isn't too populated. In large cities or 25 man raids I'm anywhere from 40-55 fps. Anyways, my fps will randomly drop to 3-4 and stay there for about a minute or so and then go back up to the low 70s. I have no clue what could be causing this. Any help is appreciated!

This never happened before I quit playing, this is something entirely new.

[Fuzzykins]

Update your drivers for your video card.
Make sure shadows are on low.

[Visioned]

In all honesty, it sounds like an application running in the background doing some random processing. Anti-viruses like Mcafee and Norton 360 do background processes often. If you don't use those, check on other apps that are running in the background.

Your video drivers could be out of date, but you would see performance drop from the first minute you log into the game so I'm pretty sure that isn't the cause.