The name OCCT comes from OverClock Checking Tool. This application will let you benchmark and overclock your system components. OCCT is the most popular all-in-one stability check and stress test tool available.

It generates heavy loads on your components while checking for errors, and will detect stability issues faster than anything else. OCCT embeds HwInfo's monitoring engine to get precise readings and diagnose issues faster.

Can I use OCCT to benchmark my CPU and GPU?

OCCT is primarily a stress test tool used for checking stability issues. With this program you can stress test your CPU, GPU and determine the memory usage on your system. You can configure the app to stop the test when the temperature is too high or when it finds any error so you can prevent hardware failures.

How long does it take to run an OCCT benchmark?

With OCCT you can run stability tests on your hardware from one minute to as long as ten hours. However, it is advisable to stress test your CPU for at least an hour.

Is OCCT free?

OCCT is free for personal use, but some features such as the Stability Certificate are reserved for paid users. For commercial use there are paid versions that start at $5 per month that include more features such as unlimited time duration.

Features

  • Up to 16-core support ( for instance, up to a Quad-Kentsfield or an Octo-Conroe )
  • Customizable tests ( Duration, Priority, CPU or RAM, ... )
  • CPU and Motherboard detection
  • Monitoring support through 3rd party application ( i.e. MBM5, Speedfan and Everest Ultimate Edition 3.50 or above )
  • Can produce graphs showing temperature and voltages during the test : Unique feature !
  • Multi-language support

Don't let your work go to waste

Ensure your computer is stable before working on your beloved projects - don't let a reboot or memory corruption put your hard work to waste

Is this a game bug or my computer?

Find out by stress-testing your components. If anything's wrong, OCCT will pick it up and tell you ! By having a wide-range of test integrated, you'll be able to pinpoint which one is faulty.

Stop wasting time with after-sale services

Find out which component is faulty and gain time by giving after-sale services proof your hardware is faulty. I don't promise you it'll go smooth, but at least, you'll have backup.

Modern monitoring dashboard

Create easy-to-read, attractive monitoring dashboards showing how your component is behaving in real-time.

Check your cooling

OCCT test will make your components go all out. If anything is wrong with your cooling, you'll quickly know.

The ultimate CPU test

OCCT's CPU test gives you full control on which core is tested - Cycle through cores, know which one generated an error, invert them... Lots of fun there.

Squeeze every MHz of your components

OCCT will help you pinpoint ideal values for your overclocked components and ensures rock-stable day-to-day usage.

What's New

  • Monitoring: Updated engine
  • CPU. Fixed: Sync issue between threads that should load the same physical core ( Thanks artemus ! )
  • Fixed: A lingering process was present when you tried to start OCCT twice
  • Monitoring: Added Snapshot polling support. This allow HwInfo to more accurately get the CPU frequency and uses much less CPU cycles to do so. Enabled by default.
  • Linpack Fixed: During stability certificates, errors were properly detected and reacted upon, but failed to show in the log and indicator
  • Linpack Fixed: error count in the log would repesent the total numbers of errors detected and not the new error count
  • Memory Fixed: Final fix to the GUI slow updates during Memory stress tests
  • Enterprise Fixed: when maximized, the test names were missing from the period display. What a weird bug to be honest.
  • Enterprise. When a single period is present in a schedule, the delete and move buttons are now hidden (they didn't do anything anyway)
  • UI Fixed: Some translations issues on Stability certificate descriptions and tooltips
  • UI: Improvements on disk-related tasks to improve UI reactivity under high load scenarios
  • Memory. Fixed: The memory test in Auto thread modes could result in very large hangs on the GUI side.
  • Memory. Fixed: The test was not properly "killing itself" when the GUI was crashed
  • Report. Fixed: In the report, 3D adaptive was using its internal name when displayed in the period selection combobox
  • Report. Fixed: selecting a 3D Adaptive period in the period selection area was outputting errors
  • Report. Fixed: The default report filename wasn't properly formatted
  • Main. Fixed : debug code reached production and generated errors on the CPU test. Sorry.
  • Main. Added proper error messages when HwInfo cannot be initialized or when OCCT cannot write in the temp folder
  • Main. Fixed : OCCT was refusing to start on setups without proper OpenCL support - which is usually due to missing or very old drivers
  • UI. Fixed: Coolermaster UI related glitches ( thanks Serhii ! )
  • StabilityCertificate. Fixed: Forgot to remove 3D adaptive from the list of benefits in the stability certificate section
  • Benchmark: Fixed : the latency benchmark would fail to give bandwidth figure in some cases due to a large page error
  • Main: Removed dependencies to windows cryptographic functions
  • Main: Upgraded from avalonia 0.10 to 11
  • UI: Replaced the "busy" indicator with a new one to lower the UI usage by using a 2FPS animation for this indicator. Especially useful for the new memory latency benchmark
  • Monitoring: Updated HwInfo engine to the latest version
  • Monitoring: Much better support for the top-level bar for AMD GPUs (some sensors were missing previously)
  • SysInfo: Added storage information
  • Settings: OCCT now allows you to disable monitoring again, as in v11
  • Cpu: Revamped the advanced thread section ! The CPU test will allow you to do per-core testing, exclude core, and ecven launch several threads per core. This will definitely get you covered for all your per-core testing needs !
  • Gpu3DStandard: Fixed issues with multi-GPU support – will now work flawlessly
  • Gpu3DAdaptive: Fixed issues with multi-GPU support – will now work flawlessly
  • Gpu3DAdaptive: Test is now available in the Free edition of OCCT
  • Vram: Fixed the GPU selection algorithm and this test will now work on GPU that aren't 3D capable ( Nvidia A100, etc.)
  • Benchmark: New benchmark : Latency/Bandwidth ! This test will tell you latency, read and write bandwidth for Memory, L1, L2, and L3 cache