The recent v1.1 patch for Quake 4 has delivered support for Hyper-Threading and Dual-Core CPUs, however this feature is bound to the Windows operating system. Even so, Linux users can rejoice as the new patch appears to provide a boost in the games performance.
"Even though the Linux port remains to support any multi-threaded functions, we were incredibly surprised with the significant performance boosts demonstrated by this game. We will continue to investigate the Quake 4 v1.1 findings we have encountered today and will continue to deliver additional reports permitting any substantial findings. On top of the possible performance boosts, there are also quite a few of noticeable in-game changes for multi-player and single-player modes. We hope the next Quake 4 Linux patch will address the multi-threaded capabilities."
The thing with the v1.1 patch though, is it's been pulled by iD Software. There's a problem with widescreen modes that could damage your monitor. We suggest you either remove the patch, or atleast not use widescreen if you wish to keep the game patched.