With recent Avid versions you can automatically promote all older Sapphire versions to Sapphire v9 AVX2. In some cases you can instead leave older Sapphire versions installed on your Avid so they will continue to be used when sequences with those versions are loaded. This is appropriate for Avid versions prior to 2.8 that do not support promoting AVX1 to AVX2.  Sapphire v2 AVX2 and v3 AVX2 should always be promoted automatically to v9 AVX2, and these two versions should not be installed at the same time.