(Dual Chip ConnectX®-4 Lx EN. - Gigabyte CLN4C44. - Firmware updates available from Gigabyte. This is effectively 2 cards glued together -PCI-E bifurcation is required to access all four ports! - If you just bung it in, the system only sees the first part and only half the ports will work, as a regular dual port card :).
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