Hyper Threading FAQ

List of Hyper Threading Frequently Asked Questions.

What is Hyperthreading?
Is HyperThreading worth the extra £80 or $100?
When to enable or disable Hyperthreading?
What are the advantages of Hyperthreading?
What are the disadvantages of Hyperthreading?
Does HyperThreading hurt performance?
Does disabling Hyper-Threading increases performance?
Enable HT vs disable HT ???
Why should I even care about hyper-threading?
How to enable or disable Hyper Threading on an Intel CPU?

What is Hyperthreading

Hyper-threading (officially Hyper-Threading Technology or HT Technology, abbreviated HTT or HT) is Intel’s term for its simultaneous multithreading to improve parallelization of computations (doing multiple tasks at once) performed on PC microprocessors. For each processor core that is physically present, the operating system addresses two virtual or logical cores, and shares the workload between them when possible. The main function of hyper-threading is to decrease the number of dependent instructions on the pipeline. In short, a Quad Core without HT (e.g. i5 CPU) has (4 cores / 4 threads) whereas a Quad Core with HT (e.g. i7 CPU) has (4 cores / 8 threads).

Is HyperThreading worth the extra £80?

If you are mostly using your PC for gaming, its not worth the cost as PC Games does not utilize more than 4 threads. A Quad Core CPU (4 cores / 4 threads) is sufficient for most high-end games whereas a Dual Core CPU with HT (2 cores / 4 threads) will be on par of Quad Core CPU. You don’t need to spend extra money on HyperThreading (HT) unless you frequently use these 32/64 bit software for work / entertainment / hobby listed below.
Video Editing: Adobe Premiere, Sony Vegas, MeGUI x264, Handbrake, Avidemux
3D Creation: Blender
Photo Rendering: Adobe Photoshop
Digital Audio Workstation: Sonar X1
File Compression: 7Zip, WinRAR, WinZip
Encryption: TrueCrypt

HT software improves productivity by 25% at most. Assuming a non-HT Quad Core takes 60 minute to encode a video, it would take approximately 48 minutes with HT, saving 12 minutes of electricity bill per video encode. This savings sums up if you use the PC for 2-6 years before upgrading to Intel’s next Tick/Tock CPU or migrate to AMD CPU if they come up with a better performance CPU against Intel.

When to enable or disable Hyperthreading?

For CPU HT owners, they would disable it for gaming and light daily usage (surf web / download-upload files / perform office paper works) and enable it for heavy usage (folding / encoding / distribute-computing). Disabling HT allows you to overclock at higher stock speed by an extra of 100-200 Mhz or have the temperature down by 4-5 degree Celsius on idle and 10 degree Celsius on load when running heavy applications or testing it via Prime95. Disabled HT also improves games FPS by 3-5 Framerate Per second and increases performance of other applications by a mere 1-5%.

To summarize, if your CPU supports Hyperthreading, you will have the ability to turn it on/off depending on your usage. However, it’s best to just leave it on always because in real-life scenario, most people tend to multi-task (performing 2 or more task simultaneously). For example, encoding video while playing Skyrim or playing your music player and working on your school assignment or surfing the web and opening/switching multiple browser tabs etc. Hyperthreading provides a better PC usage experience by approximately 10% of non-HT CPU.

What are the advantages of Hyperthreading?

You gain at most 25% from applications that makes use of Hyper Threading Technology (HTT). Some HT applications might get as high as 30% and some others as low as 5%. Games with low-medium settings gain additional performance boost since mostly its relying on CPU instead of GPU, whereas Ultra High Settings, the Hyper Threading benefits does not kick in as reported by i7 HT-CPU owners.

What are the disadvantages of Hyperthreading?

The HT process does generate extra heat. Physical cores are forced to perform more calculations per cycle, and thus have more leakage. More leakage means more heat which negatively impacts overclocking, but given memory bottlenecks may actually provide much more processing power in highly threaded applications.

Does Hyper-Threading hurt performance?

Yes and no to certain extents. If 80% of the time you run non-HT applications, then you won’t see the increase performance as compared to switching your OS (Operating System) installation from a HDD (Hard Disk Drive) to a SSD (Solid State Drive). If you run long hours of heavy threaded applications such as encoding video + streaming live + recording + etc, then you will notice that slight performance increase.

Does disabling Hyper-Threading increases performance?

It depends on what application you run and how long it runs. For instance, a core i7 CPU such as Sandy Bridge 2600K or Ivy Bridge 3770K with Hyper Threading enabled will save more time on completing lengthy duration tasks such as compressing hundred of files, compiling large-coded software with Java Netbeans or Microsoft Visual Studio, encrypting files, encoding HD video or lossless/lossy audio, 3D Animation, etc compared to playing music on Windows Media Player, watching movies or doing paper work on Microsoft Office software. Disabling Hyper Threading in this scenario will backfire your goal in achieving higher performance. Instead of getting stuck between the question of enabling or disabling, it would be advisable to think over on what are your current needs. If mostly gaming, go with a non-HT Intel CPU to save some cash.

Enable HT vs disable HT ???

Short answer – No. Ask yourself this question: Why purchase a Hyper Threading CPU that costs extra $100 USD but later question yourself about whether to disable that feature? Wouldn’t it be best to grab a non-Hyper Threaded CPU to save some cash or invest in other PC components? Check out the advantages and disadvantages of Hyperthreading above.

Why should I even care about hyper-threading?

Hyper Threading makes a difference when creating content such as perform video encoding/decoding or rendering 3D objects or heavy-duty audio. Otherwise, you will see almost zero benefit when using regular applications day in and day out.

How to enable or disable Hyper Threading on an Intel CPU?

Restart your PC and get into yoru BIOS Setup Utility or UEFI (Motherboard), scroll down to CPU Config using arrow keys or mouse, and you will notice an option called Intel (R) Hyper Threading Technology [Enabled], change the settings using arrow keys, and hit F10 to Save and Exit. Some motherboards have it set the option keys differently so check out your motherboard manual book.

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2 thoughts on “Hyper Threading FAQ

  1. wvxvw

    You did not mention inverting a ten millions by ten millions matrix in Matlab!!! It will spend all the system resources you can get and will be asking for more. 😀

    Anyways, a nice article. Thumbs up, hope you aren’t compiling huge Java NetBeans projects, but use HT properly for encoding animations 🙂

  2. Cracker's Way

    GREAT BLOG!
    prompt for you!!!