Windows XP lag

Describe the problem. Be as specific as possible!:
My windows XP computer is back to the stuttering - but now it's mucho unplayable, 1 second smooth, 1 second without frame updates.

I defragmented the MS folder and restarted, what I see is if I hold up my watch to the monitor, every time the second ticks over, it switches from updating frames to not updating frames and vice versa.

It's a 2.8GHz P4, only place it ever used to dip below max framerate is FM1CH1 and Boomers.



Win 7 computer is seeing the same oscillations in CPU usage but it's not affecting the framerate.

im having this issue too since v1.07 (on my XP desktop) ;[ i was running perfectly fine before the patch. my other 2 laptops (vista and 7) run without lag, so it isn't my internet issue.

they broke XP again ;[ i remember they broke it once before too T_T

--------------- edit ----------------
yay watever they did in the unscheduled sc fixed my lag <3 now im lag free on all comps