BUILD 16.1.10.99 Windows & Linux
No-Cost PC Reliability Workbench

Serious Hardware Reliability Toolkit

OCCT lets you watch live sensors, run punishing workloads, and export evidence that your machine stays stable when it matters.

Get OCCT Free
70M+ Downloads
20+ Years in development
Win & Linux Dual platform
Millions Validation runs

Why choose OCCT?

A trusted path to rock-solid hardware checks

OCCT loads every critical lane—CPU, GPU, memory, and power—with synchronized telemetry and audit-ready reports used by builders worldwide.

Full-System Load Coverage

Tune CPU, GPU, RAM, and PSU scenarios with granular controls and catch silent faults before they reach production.

Live Sensor Command Center

Follow temperature, voltage, clock, and load curves in real time with Hwinfo hooks and proactive overheat warnings.

Scores and Stability Proofs

Rank CPU and memory performance, then publish shareable stability certificates your team can trust.

OCCT testing capabilities

Screenshot of OCCT multi-component stress configuration panel

Processor Torture Profiles

Find CPU weak spots before users do

Multi-threaded engines surface throttling, voltage droop, and hidden errors long before everyday apps complain.

  • Adjustable threads and instruction mix
  • Errors flagged within seconds
  • Coupled thermal and power telemetry
See CPU load options
OCCT adaptive 3D GPU scene with shaded geometry under load

Graphics Pipeline Pressure

Stress GPUs the way games and renders actually do

Adaptive 3D scenes and compute shaders hammer VRAM, shaders, and VRMs—exposing artifacts static benchmarks ignore.

  • Adaptive 3D renderer
  • OpenCL plus compute shader paths
  • VRAM and hotspot tracking
Browse GPU stress modes
OCCT memory suite showing preset controls in version 17

RAM Integrity Drills

Catch memory faults before they wreck data

Pattern libraries, presets, import/export, and block-level control—built for overclockers, integrators, and data-sensitive rigs.

  • Preset slots with import/export
  • Block allocator tuning
  • Version 17 throughput upgrades
Review memory test tools
70M+ Downloads
20+ Years
4 Stress engines
24/7 Live sensors

Relied on Worldwide — Two Decades, 70M+ Installs

Players

Whether you chase clocks, esports stability, sim rigs, or VR, OCCT keeps frames smooth when silicon runs hot.

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Pro & Prebuilts

Stability isn't optional. Ideal for PC builders, RMA technicians, and high-performance computing: OCCT has you covered for your infrastructure, employees and customers.

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Enterprise Floors

Computers play a pivotal role in production chains where interruption is not allowed. Elevate your industrial operations with OCCT's performance and stability solutions.

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Why OCCT stands apart

See why teams pick OCCT instead of generic burn-in toys or bare-bones monitors.

Feature OCCT Prime95 FurMark HWiNFO AIDA64
CPU + GPU + RAM + PSU testing Yes CPU only GPU only Monitor only Partial
Integrated real-time monitoring Yes No Limited Yes Yes
3D adaptive GPU testing Yes No Static No No
Stability certificates Yes No No No No
Report comparison tool Yes No No No Limited
GPU compute / OpenCL stress Yes No No No No
Linux support Yes Yes No Yes Limited
Completely free Yes Yes Yes Free tier Paid
Community voices

Community-rated 5/5 with more than seventy million installs and counting.

"Best overclocking tool I have ever used. The monitoring integration and detailed reports make troubleshooting hardware issues straightforward."

dappervoid

"I use OCCT on every custom build before shipping to customers. The stability certificates are a professional touch that sets my shop apart."

PC Builder Pro

"The 3D adaptive testing caught GPU artifacts that FurMark missed entirely. OCCT is now my go-to for any GPU checks workflow."

Hardware Enthusiast

"Report comparison saved me hours diagnosing a throttling issue. I spotted a misconfigured memory timing in seconds that took days with other tools."

System Administrator

"Linux support is a game changer for our data center burn-in process. Same reliable testing suite across our entire fleet."

Infrastructure Engineer

"GPU compute testing validated my AI training rig before I committed to a week-long model run. Caught a failing card immediately."

ML Researcher

Different Jobs, Several Editions

Pick the lane that fits your workflow

Select the OCCT edition you need

Every edition is free—match the toolkit to how you validate hardware.

Personal

For hobbyists and players

Free

  • CPU, GPU and RAM stress tests
  • Real-time monitoring
  • Windows support
Install Free

Enterprise

For racks, labs, and fleet QA

Free

  • Full Linux support
  • GPU compute / OpenCL
  • Fleet burn-in workflows
Open Linux Package

Enterprise+

For large-scale rollouts

Contact

  • All Enterprise capabilities
  • Priority support channels
  • Custom deployment utilities
Learn More
Common Questions
OCCT (OverClock Checking Tool) is used to stress test, benchmark and monitor computer hardware. It validates CPU, GPU, RAM and power supply stability under heavy loads, helping users detect overheating, voltage drops, frequency throttling and hardware defects before they cause system failures.
Yes. OCCT is free software with full access to stability testing, monitoring, benchmarking and certificate features. Multiple editions exist for different needs, but core diagnostic capabilities remain accessible without cost.
Stress testing software intentionally pushes hardware to extreme limits, which can trigger heuristic false positives in antivirus engines. OCCT is not malware. Always verify downloads using published SHA checksums and download only from official sources. See our antivirus guide for step-by-step instructions.
Yes. OCCT brings its full suite of stability testing, monitoring and benchmarking features to Linux, making it suitable for data centers, embedded systems and high-performance computing environments.
Browse all questions

Ready to pressure-test your rig?

Install OCCT today and document how your hardware behaves under sustained load.

Get OCCT Free