There seems to be a widespread misconception that the APPLICATION must be multithreaded in order to achieve ANY gain from Multi-Processor, Multi-Core, or Hyerthreading. This is not true. If the OS is multiprocessor capable then SOME gain is achieved, whether or not the individual processes or applications are (multithreaded that is).
In a windows environment, even before you launch [insert your favorite game title here] there are many system, utility, and service processes running. The OS is capable of distributing these processes across the multiple processor instances (whether they be physical or logical), thus lowering the impact of these "overhead" processes on your favorite game.
We can take it a step further by setting the process to processor affinity with all overhead processes running only on Processor0 and setting the affinity for your game to Processor1. Or in the case of hyperthreaded multi-core/processor systems Processors 0,1,2,3, etc...
With a bit of forethought and system configuration you can achieve appreciable throughput gain with these technologies. I've been running multiprocessing systems for my primary workstation for years, and don't want to go back to single processor core. I do have to say that on average I am running OVER 70 processes and as such see a higher delta in performace than the average user.
At the same time I've been able to leverage some slower processors (P4XEON@2GHz) and achieve some very reasonable performance with the latest games.
Thats my eight cents (hyperthreaded and multiprocessored) for now.
We all know what we know, and everyone else knows we're wrong.
Ad Astra Per Aspera
(A rough road leads to the Stars)
We all know what we know, and everyone else knows we are wrong.
System Specifications in BIO