In general, Arnold is going to work on pretty much any 64-bit system where Houdini, Maya, Cinema 4D, 3ds Max, Katana, or Softimage works. However, there are some minimum OS requirements:
- OSX 10.8 or later
- Windows 7 or later, with the Visual Studio 2015 redistributable
- Linux with at least glibc 2.12 and libstdc++ 3.4.13 (gcc 4.4.7). This is equivalent to RHEL/CentOS 6
- CPUs need to support the SSE4.1 instruction set
Other than that, Arnold works on Intel and AMD processors, and for rendering, has no graphic card or GPU requirements, since Arnold is a CPU-based renderer.