The ultimate stability diagnostic

Test every component of your PC using 6 powerful, efficient tests ! CPU, Memory, GPU, VRAM, Power supplies, every critical component can be tested.

Available for free...

...for personal use only, and with a few limitations. Yes, we are shooting ourselves in the foot. Badly. And it hurts ! But we count on you to support our work !


View the insides of your computer using OCCT's built-in monitoring and system information engine, based on the award-winning engine HwInfo64.


Done overclocking ? Compare your results using OCCT's built-in benchmarks for CPU and Memory ! ( More coming soon )

Protect your computer

Even if components are nowadays well protected against overheating, OCCT includes another layer of security by allowing you to set a maximum temperature threshold.

The most advanced CPU test available

OCCT's CPU test is the most advanced out there. Capable of detecting stability issues in seconds, it can do per-core testing and allow you to customize the instruction set used and the data size. You're an expert ? Look no further.

A displayless, customizable 3D test

Need to test GPUs without a display, like in your cryptomining farm ? OCCT has the only 3D stress test that runs without a display attached. You can also limit the 3D test load to stay under the limits of your particular GPU.

Fully portable

No installer or useless stuff like this. OCCT is a single-file executable. Whether it is on your desktop, a USB flash disk, or a network folder, OCCT will run with a simple double-click !

Only for

All limitations removed

All the limitations of OCCT Personal will be removed. No waiting time between tests, and the test duration is now unlimited ! Remember : a Pro or Enterprise license is required for professional and commercial use of OCCT.

Test report

At the end of a test, you will be able to save a full graphical report of what happened during the test, for diagnostic purposes.

Requires a Pro license

Professional and Business use allowed

The Pro and enterprise versions allow commercial usage of OCCT. Oh yes, and if you're wondering how many licenses do you need, here's the answer : only one !

CSV export

Build your own graphs using the CSV export ! At the end of a test, when saving a report, OCCT will output a CSV file containing all monitoring figures read during the test.

Requires an Enterprise license

Test chain

Build a comprehensive, complete stress test suited tailored to your needs ! OCCT will execute the supplied tests in succession, having a full diagnostic of the PC in a click

HTML report

Compare different runs and keep a trace of everything that occured during a test schedule with a full, single-file HTML report everything system information, test results, monitoring data in dynamic graphs.

GUI automation

Tired of clicking Start in OCCT ? Use command-line arguments to automate the OCCT's GUI. It'll start a test automatically, close itself, save the report where you want it to be...

Requires an Enterprise license

Full-featured command-line client

Ever wanted to run OCCT unattended ? Use the command-line edition, launch a test schedule using a batch file, and do something else while it runs !


OCCT Command-line is the lightest edition of OCCT. No GUI, no fancy stuff, leaving all the computing power to stress testing.

Stability testing since 2003

OCBASE/OCCT - Adrien Mercier

80 rue de l'abbé de l'épée

59500 Douai