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OCCT 4.5.1

OverClock Checking Tool

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OCCT screenshotOCCT is a stability checking utility that was developed back in 2003, and was constantly updated since. It permits you to entirely test your PC's stability, using four different tests: CPU:OCCT and CPU:Linpack aimed at examining the CPU, GPU:3D for the GPU strength, and Power Supply, a mix of CPU:Linpack and GPU:3D to completely load your Power Supply.

Each test can be used indefinitely, or for a determined amount of time. You can even add an idle period at the start or at the end of a test, to better understand how your PC's temperature ascent from an IDLE state to entirely loaded, and the other way round.

OCCT also integrates a monitoring engine, offering you full readings of the PC's inner temperatures, voltages, and fan acceleration, and shows them both in graphs in real time and at the end of a test. If you are concerned about strength with the real time graphs, don't: even if they are very light, just concealing the graph panel will stop them from refreshing.

OCCT even defends your PC from overheating or damage by adding alarms you can change for each sensor: once you go over (or under) the alarm amount for a voltage, temperature, or fan speed, the test will stop to conserve your computer.


  • Includes various tests for PC performance and stability.
  • Integrates an advanced hardware monitoring engine.


  • CPU tests may take some time (at least one hour).
  • It's hard for beginners to fully understand of results.
Version 4.5.1
Developer | see all products from this developer
Product Homepage OCCT
License Free (Freeware)
Last Week Downloads 2
All Time Downloads 4,416
Filename OCCTPT4.5.1.exe
Filesize 7.8MB
MD5 Checksum 1375A2357431BCB928334068297B5266
OS Support Windows All
Category Utilities

100% CLEAN Certification

BadgeOCCT has been tested by team against viruses, spyware, adware, trojan, backdoors and was found to be 100% clean. Our editors will recheck this software periodically to assure that it remains clean.


Old Versions

Software Date Added
OCCT 4.5.1 August 21, 2017 - Latest Version
OCCT 4.5.1 Beta 01 July 03, 2017
OCCT 4.5.0 June 30, 2017
OCCT 4.4.2 May 05, 2016
OCCT 4.4.1 September 22, 2014

Download the free OCCT