Most tech enthusiasts of the era eventually concluded that the Microsoft Hotfix was the "correct" fix for the operating system scheduler. However, AMD recommended installing the Optimizer in addition to the hotfix. Many users found that the Optimizer provided an extra layer of stability for specific game engines (like Battlefield 2 or Quake 4 ) that the Windows patch alone didn't fully resolve.
"See that stutter? That choppy, erratic movement? That isn't a bad GPU. That's history trying to break your PC. Back in 2005, AMD released the Athlon 64 X2—a processor so ahead of its time that Windows didn't know how to talk to it. Today, we're diving into the AMD Dual-Core Optimizer: the tiny patch that saved gaming on dual-core CPUs." amd dual core optimizer