Not sure if this has been answered already, but many micro stutters are monitor related (even more, TV related if you use a TV instead of a monitor).
V-Sync will partially solve the problem and here is why:
If your PC sends more frames than your monitor is able to refresh, the FPS might be constant for the GPU, but will not be for the Monitor/TV.
This issue is also responsible partially for screen tearing.
In most cases, if you are running games at 30-40 frames, those problems wont appear, since the tv/monitor can handle the load VERY easy, and your brain adjusts to that frame speed.
If the frames remain stable, you will feel it like fluent gameplay.
On the flipside, if you are running at say 100 fps, and the monitor can manage 60, it will NOT manage always 60 (electornics in this term are not that precise).
It will unfortunately, sometimes repeat a frame, and sometimes get a new one (and in some cases, even give a frame, tear the screen since it updates the next frame is too fast, and then repeat the second frame, creating micro stuttering).
If this is the problem you are having, try to increase your Anti aliasing or your in game settings until your max frames stay under 60 (this is the most common monitor/tv speed).
Bare in mind that LED based monitors and tvs refresh frames from top to bottom, making these issues appear more pronounced (thats why i bought a plasma tv, even if image retention can be a bitch for gaming if you are not very, very careful about it).
Let me know if this is the problem or if not, then we will see what can be the cause.
Kind Regards,
The cat.