System Requirements

Current Versions: Fathom 15, Arrow 12, Impulse 12, & xStream 5

Operating System

  • Windows 11 (x86-64 only; ARM not supported), recommended to use latest version from General Availability Channel

  • Windows 10 (x86-64 only; ARM not supported), recommended to use latest version from ESU program

  • Windows Server 2025 / 2022 / 2019 / 2016 (Note: client/server deployment setup is no longer supported. Server editions are listed here only for virtual machine environments.)

Hardware

  • Processor: x86-64 (64-bit) architecture is required, and FMA3 instruction support is advised*

  • RAM: 4 GB minimum (in addition to OS requirements)

  • Disk Space: 25 GB+ recommended** (SSD preferred for faster read/write operations with output data)

  • Display: 1024 × 768 or higher (1080p recommended)

  • Input: Pointing device (mouse, touchpad, etc)

* FMA3 instruction support is advised. Without FMA3, the software falls back to sequential multiply-add operations, which are slower and introduce additional rounding error. In testing, this rounding error has been shown to cause convergence failures in sensitive models. CPUs predating Intel Haswell (2013) or AMD Piledriver (2012) do not support FMA3.

** Full installations of all four applications takes approximately 2-3 GB, plus sufficient working space for model/output files is needed. Size of output files can vary significantly by product, model complexity, and number of scenarios included in the analysis. Impulse and xStream in particular can have individual output files (one per scenario) that take multiple GBs.

Licensing & Network Requirements

A valid license login is required for the applications to be accessible.

  • For standard installations you will need internet access (licensing will be validated by pinging https://datacor.license.nalpeiron.io).

  • For air-gapped networks refer to the Local License Server (LLS) installation.

Administrator Rights for Installation

Administrator rights on the system are required for installation.

Microsoft Excel

Certain features within the software require Microsoft Excel; however, you don't necessarily need to use these features. If you do want to use these features which relate to importing/exporting data more easily, then we recommend using the latest version of Excel from Microsoft 365, though previous versions may work fine. Features include: Excel Export Manager, Import Excel Change Data, Cost Library Excel import/export, Multi-Scenario Pump vs System Curve Excel Export.

 

Previous Versions

Requirements for older product versions are listed below. For all previous versions the RAM, disk, display, and input requirements are the same as listed under the Current Versions section above. Processor requirements differ: the FMA3 and 64-bit (x86-64) requirements apply only to Fathom 15, Arrow 12, Impulse 12, xStream 5, and newer. Previous versions ran on both 32-bit and 64-bit systems.

Fathom 14, Arrow 11, Impulse 11, & xStream 4

  • OS: Windows 11, 10, 8.1, 8, or 7 (not RT editions), 32-bit or 64-bit

  • Server OS: Windows Server 2025 / 2022 / 2019 / 2016 / 2012 / 2012 R2 / 2008 R2

  • .NET: Framework 4.8 or later (separate install required)

Fathom 13, Arrow 10, Impulse 10, & xStream 3

  • OS: Windows 11, 10, 8.1, 8, or 7 (not RT editions), 32-bit or 64-bit

  • Server OS: Windows Server 2022 / 2019 / 2016 / 2012 / 2012 R2 / 2008 R2

  • .NET: Framework 4.8 or later (separate install required)

Fathom 12, Arrow 9, Impulse 9, & xStream 2

  • OS: Windows 11, 10, 8.1, 8, or 7 (not RT editions), 32-bit or 64-bit

  • Server OS: Windows Server 2019 / 2016 / 2012 / 2012 R2 / 2008 R2

  • .NET: Framework 4.8 or later (separate install required)

Fathom 11, Arrow 8, Impulse 8, & xStream 1

  • OS: Windows 11, 10, 8.1, 8, or 7 (not RT editions), 32-bit or 64-bit

  • Server OS: Not specified in original documentation

  • .NET: Framework 4.8 or later (separate install required)

Fathom 10, Arrow 7, & Impulse 7

  • OS: Windows 10, 8.1, 8, or 7 (not RT editions), 32-bit or 64-bit

  • Server OS: Not specified in original documentation

  • .NET: Framework 4.7 or later (separate install required)

Fathom 9, Arrow 6, & Impulse 6

  • OS: Windows 10, 8.1, 8, or 7 (not RT editions), 32-bit or 64-bit

  • Server OS: Windows Server 2022 / 2019 / 2016 / 2012 / 2012 R2 / 2008 R2

  • .NET: Framework 4.0 or later

Fathom 8, Arrow 5, & Impulse 5

  • OS: Windows 10, 8.1, 8, or 7 (not RT editions), 32-bit or 64-bit

  • Server OS: Windows Server 2003 (SP2) / 2008 / 2012 or later

  • .NET: Framework 3.5 or later