Hola Boricles: // SetPriorityClass: de mayor a menor prioridad
// REALTIME_PRIORITY_CLASS
// HIGH_PRIORITY_CLASS
// NORMAL_PRIORITY_CLASS
// IDLE_PRIORITY_CLASS
// por ej.:
SetPriorityClass(GetCurrentProcess(), REALTIME_PRIORITY_CLASS);
// SetThreadPriority: de mayor a menor prioridad
// THREAD_PRIORITY_TIME_CRITICAL
// THREAD_PRIORITY_HIGHEST
// THREAD_PRIORITY_NORMAL
// THREAD_PRIORITY_LOWEST
// THREAD_PRIORITY_IDLE
// por ej.:
SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_TIME_CRITICAL);
Saludos.