System Stability Tester for Linux (64-bit) is free and open source software that tries to test the system's stability by calculating up to 128 millions of Pi digits. It supports multiple calculation algorithms and calculates up to 128 million digits of Pi. It can recognize the CPU model, manufacturer, and operational frequency. Compare the calculation results of all the threads after each step and issue a warning if something went wrong. Run continuously for up to 50 turns and log the results after each step and each turn and record the calculated digits of Pi in a human readable text file. It also provides checksum validation over the result.