We initially covered Hyper Threading (and its performance) in our P4 3.06 GHz review but are returning to the topic for additional in-depth testing on Intel’s newest CPU technology. As we discussed in Part I, Hyper Threading’s potential to affect performance across the entire spectrum of x86 32-bit based programming is both a blessing and a curse. On the one hand, HT has been shown by this and other sites across the ‘Net to grant large performance increases in certain applications—but, unfortunately, such performance gains are not guaranteed. Certain applications and performance situations have shown no gain with Hyper Threading activated and some have shown a marked decrease. This article will discuss several system variables we’ve found can impact Hyper Threading performance as well as examining the impact HT has on several popular distributed computing clients.