Great Internet Mersenne Prime Search and GIMPS for Windows PC

Prime95

Browse by Company

Adobe, Apowersoft, Ashampoo, Autodesk, Avast, Corel, Cyberlink, Google, iMyFone, iTop, Movavi, PassFab, Passper, Stardock, Tenorshare, Wargaming, Wondershare

Prime95 29.8 Build 3 (32-bit)

  -  5.38 MB  -  Freeware
Free Download

Security Status

Sometimes latest versions of the software can cause issues when installed on older devices or devices running an older version of the operating system.

Software makers usually fix these issues but it can take them some time. What you can do in the meantime is to download and install an older version of Prime95 29.8 Build 3 (32-bit).


For those interested in downloading the most recent release of Prime95 or reading our review, simply click here.


All old versions distributed on our website are completely virus-free and available for download at no cost.


We would love to hear from you

If you have any questions or ideas that you want to share with us - head over to our Contact page and let us know. We value your feedback!

Download Prime95 29.8 Build 3 (32-bit)

  • Prime95 29.8 Build 3 (32-bit) Screenshots

    The images below have been resized. Click on them to view the screenshots in full size.

    Prime95 29.8 Build 3 (32-bit) Screenshot 1
  • Prime95 29.8 Build 3 (32-bit) Screenshot 2
  • Prime95 29.8 Build 3 (32-bit) Screenshot 3
  • Prime95 29.8 Build 3 (32-bit) Screenshot 4

What's new in this version:

- Since GPUs are so much better at trial factoring than CPUs, benchmarking no longer times prime95's trial factoring by default. Two new benchmarking options are available: OnlyBenchThroughput and OnlyBenchMaxCPUs. See undoc.txt for details.
- Slightly reduced the memory bandwidth requirements for several large FFTs. May lead to a very small speed increase for users testing 100 million digit numbers.
- If running more than worker, prime95 looks for any sin/cos data that it can share among the workers. Depending on the FFT sizes you are running, this could lead to a very slight reduction in needed memory bandwidth.
- Method for choosing the best FFT implementation changed. In previous versions, the FFT implementation that resulted in the fastest single worker timing was used. In this version the FFT implementation that had the best throughput was selected. For FMA3 FFTs I used a 4-core Skylake to measure best throughput. For AVX FFTs I used a 4-core Sandy Bridge to measure best throughput. Not many FFTs were affected, but you may see a few percent variation in throughput with this version.
- Improved AVX2 trial factoring in 64-bit executable. Trial factoring should still be done on a GPU. A GPU is on the order of 100 times more efficient at trial factoring than a CPU!!!
- Trial factoring now defines one "iteration" as processing 128KB of sieve, or 1M possible factors. In previous versions an iteration was defined as 16KB of sieve in 32-bit executables and 48KB in 64-bit executables. The trial factoring benchmark still times processing 16KB of sieve.
- Trial factoring in 64-bit executables is now multi-threaded.
- On initial install, the default settings for number of worker windows will be set to the number of cores / 4 with multithreading turned on.
- The worker windows dialog box now enforces a minimum number of multi-threaded cores for some work types to ensure timely completion of assignments. Also, the worker windows menu choice no longer allows assigning work to hyperthreads (they are rarely beneficial in prime95).
- This behavior can be overridden with the ConfigureHyperthreads undoc.txt feature.

Top Downloads

More Popular Software »