This looks like a cool listing. The CX3 is not necessarily the best price at $29, but this one has a bracket and an internal to external SAS converter on the same bracket. That's a pretty neat way to combine slots. These internal to external SAS adapters can cost quite a bit so getting these together is not bad. I've def spent $30 on just an internal to external SAS adapter before.
CX354A W/ EXT SAS ADAPTER Mellanox ConnectX-3 VPI Network Adapter CX354A-QCBT | eBay
Notes: CX354A W/ EXT SAS ADAPTER. Add a Custom Support Contract to This Item Condition: USED.
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