Nearly all CPUs today are multi-core: they contain several processing units that can handle different tasks at once.
However, the benefits of adding more cores aren’t always spelled out. What’s the difference between single-threaded and multithreaded applications? What is Hyper-Threading, and how is it different from normal multithreading?
To explain the benefits of additional cores and Intel® Hyper-Threading Technology, let’s walk through these terms and explain what they mean when running games and everyday applications.
What Is Multithreading?
Multithreading is a form of parallelization or dividing up work for simultaneous processing. Instead of giving a large workload to a single core, threaded programs split the work into multiple software threads. These threads are processed in parallel by different CPU cores to save time.
Depending on how they’re built, games may be lightly threaded or heavily threaded. Some older game engines are known for their reliance on single-threaded performance, meaning they mostly use a single CPU core and get a major boost from higher clock speeds.
Today, game engines like Unreal Engine 4 utilize multiple cores when creating complex scenes3. Engines may also use multithreading to handle different parts of “draw calls” — instructions sent from the CPU to the GPU about in-game objects, textures, and shaders to draw.
What Is Hyper-Threading?
Intel® Hyper-Threading Technology is a hardware innovation that allows more than one thread to run on each core. More threads means more work can be done in parallel.
How does Hyper-Threading work? When Intel® Hyper-Threading Technology is active, the CPU exposes two execution contexts per physical core. This means that one physical core now works like two “logical cores” that can handle different software threads. The ten-core Intel® Core™ i9-10900K processor, for example, has 20 threads when Hyper-Threading is enabled.
Two logical cores can work through tasks more efficiently than a traditional single-threaded core. By taking advantage of idle time when the core would formerly be waiting for other tasks to complete, Intel® Hyper-Threading Technology improves CPU throughput (by up to 30% in server applications4).
Wondering how to enable Hyper-Threading? It’s enabled by default, but it can be switched on and off from the BIOS environment by setting “Hyper-Threading Technology” to “Enable” or “Disable.” Note that Intel® Hyper-Threading Technology is only available on some enthusiast CPUs: see the full list here.
What Benefits Will I See from Hyper-Threading?
With CPU Hyper-Threading, a PC can process more information in less time and run more background tasks without disruption. Under the right circumstances, the technology lets CPU cores effectively do two things at once. Multitaskers, streamers, and professionals running heavily threaded programs can boost their computing experience by upgrading to a gaming laptop or gaming desktop CPU with Intel® Hyper-Threading Technology, such as the latest Intel® Core™ i9 processor.