This works for SWBF2.. it will prolly work for SWBF1 too. Are you running dual core? You may have to turn one off and run in "affinity".
Here's the TweakGuide
. It gets into the procedure for shutting off one of the cores, as well as a few other issues for CTD. Like I said.. SWBF1 is very similar to SWBF2 so it may work.