Download OCCT 17 (x64) for free. This hardware stability test program checks your CPU, GPU, RAM, and PSU, displaying temperatures, voltages, and real-time test results to help you prepare your system for heavy use.
What is OCCT?
OCCT OCBASE (short for OverClock Checking Tool) is a comprehensive computer stability testing program developed by OCBASE since 2003. Originally designed specifically for overclockers, it has now become a standard tool for new PC builders, computer repair technicians, hardware reviewers, and gamers who want to know how well their machines can handle extreme loads.
The primary function of OCCT is to extract every ounce of power from the system's core components and detect errors or excessive temperatures. There are various test modes available depending on the component, including CPU tests using CPU:OCCT and CPU:Linpack, graphics card tests using GPU:3D, system and VRAM tests, and even a Power Supply mode that loads both the CPU and graphics card simultaneously to check for stable power supply performance. Version 13 also adds a Combined Test mode that runs multiple tests randomly to quickly identify system vulnerabilities. For graphics card enthusiasts who want a more specialized, full-featured test, there are also options available. FurMark Use the other one as well.
What sets OCCT apart from other system testing software is its built-in monitoring system. It measures various system parameters in real-time and displays them as graphs throughout the testing process. This includes CPU and GPU temperatures, fan speed, voltage, actual operating frequency, usage rate, and power consumption. This allows for immediate review of any freezes or restarts during testing to identify the culprit, as the graphs provide a clear explanation. Furthermore, it has an automatic protection system that stops the test immediately if the temperature reaches a predefined limit, eliminating the fear of damaging the system due to neglecting to monitor the screen.
After the test is complete, OCCT generates a graphical report that can be saved. This is ideal for those who need to send the results to clients or keep them for comparison with previous tests. For those who want to perform more rigorous testing, there is a Pro version that allows unlimited running times, eliminates queuing during testing, and exports reports as CSV files. The free version offers full functionality for basic testing.
Another advantage is that OCCT is a portable, single-file .exe file, requiring no complicated installation. It can be run from a flash drive at a computer repair shop. Currently, it supports both Windows and Linux and is available for free download from Steam. For those who have recently built a new computer or overclocked their CPU, running OCCT for one to two hours before actual use provides peace of mind.
Key Features
- Create simulated tasks to test the stability limits of the central processing unit (CPU).
- A tool for checking the durability of the graphics processing unit (GPU) and VRAM memory.
- Supports power supply testing to verify power delivery under heavy load.
- Real-time sensor alert system with temperature and voltage monitoring.
- The system automatically shuts down when the hardware temperature exceeds a safe level.
- It can detect microsecond-level errors that cause blue screen errors or system freezes.
- The interface displays performance results through data graphs, allowing for clear statistical analysis.
- Supports generating a test results summary report after the process is complete.
- It functions as a portable program and does not require installation on the operating system.
- The sensor database is continuously updated to support the latest computer components.
What's new
Version 17.1.9 – 2026/10/16
- Improve the reliability of the test scheduling system.
- Storage. Fixed a bug where the benchmark would freeze for 10 seconds before the test began.
- Memory. Improved memory testing for greater stability and easier code maintenance.
- Fixes an issue where the Steam version of OCCT displays the Patreon option instead of the Steam option.
- OCCT will now open normally, even if the temporary folder (temp) or the folder where the program is located has spaces in its name.
- Older AMD CPUs used sensors. TCTL/TDIE In the monitor bar at the top.
- The automatic updater will try again if the current .exe file cannot be updated because it is locked by antivirus or other program.
- The last known state has been changed to a cyclical recording method, making it more reliable and available for viewing more frequently.
- Resolves an issue where OCCT refuses to launch if the last saved state after a crash is corrupted.
file information
- Operating System: Windows 11 / Windows 10 / 8.1 / 7 (x64)
- Developer: www.ocbase.com
- License: Freeware
- Language: English
- Size: 197.18 MB
- File type: *.exe
- Installation method: Yes
- Updated: 18/10/2026
- Need to read: Download Guide
