This package NVMUpdate_Package_Silicom_145 is for PE425G4i81L-XR-NU to downgrade firmware from version 4.01.
NVMUpdatePackage_v3_00 downgrades firmware to version 3.00
NVMUpdatePackage_v3_20 downgrades firmware to version 3.20
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Operating System Support
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E810_NVMUpdatePackage_v3_20_EFI.tar.gz		- for EFI x64
E810_NVMUpdatePackage_v3_20_ESX.tar.gz		- for ESX x64
E810_NVMUpdatePackage_v3_20_FreeBSD.tar.gz	- for FreeBSD x64
E810_NVMUpdatePackage_v3_20_Linux.tar.gz	- for Linux x64
E810_NVMUpdatePackage_v3_20_Windows.zip		- for Windows x64

E810_NVMUpdatePackage_v3_00_EFI.tar.gz		- for EFI x64
E810_NVMUpdatePackage_v3_00_ESX.tar.gz		- for ESX x64
E810_NVMUpdatePackage_v3_00_FreeBSD.tar.gz	- for FreeBSD x64
E810_NVMUpdatePackage_v3_00_Linux.tar.gz	- for Linux x64
E810_NVMUpdatePackage_v3_00_Windows.zip		- for Windows x64