Hello there thinking about a simple 2 computer 10g point to point link. These are both linux machines running modern 5.2+ kernel, ubuntu 19.10. Each computer has one free pci-e 3.0 x4 slot. Which I understand can also take x8 cards if needed (with some slight modification, that I don’t mind). IDK what I am doing. and only the last choice seem like (to me) something I can reliably count on as working. Currently, my 4 main choices seems to be one of: 1) A pair of these single port cards 2x Mellanox ConnectX-3 MCX341 SFP+10Gigabit Ethernet RMDA/RoCE | eBay +1 cable Cisco 37-1150-02 SFP-H10GB-ACU10M Direct Attach 10Gb SFP+ 10M Cable | eBay = £73.60 OR 2) A pair of these dual port cards 2x Mellanox ConnectX-3 MCX312 Dual Port 10 Gigabit Ethernet RMDA/RoCE | eBay +1 cable Cisco 37-1150-02 SFP-H10GB-ACU10M Direct Attach 10Gb SFP+ 10M Cable | eBay = £99.95 OR 3) Dual link is possible? for 20GBe teamed ? 2x Mellanox ConnectX-3 MCX312 Dual Port 10 Gigabit Ethernet RMDA/RoCE | eBay +2 cables Cisco 37-1150-02 SFP-H10GB-ACU10M Direct Attach 10Gb SFP+ 10M Cable | eBay = £123.95 OR 4) Pair of AQN-107 modern Aquantia cards (RJ45) 2x US $76.95 5% OFF|LR LINK 6880BT PCIe x4 Single Port 10G Gigabit Ethernet RJ45 copper network adapter PC Express Controller lan card server Nic-in Network Cards from Computer & Office on AliExpress with existing RJ45 cat6 cabling that I already have ( which is 1000mhz, 10gb capable) = £129.45 total OR 5) Is there anything else I should be considering, that is better (=cheaper but still works) ? Another question: How can I be sure that the SFP+ cable is going to be compatible / work with those cards? It says it’s a used CISCO cable. Therefore should I be buying a MELLANOX branded SFP+ cable instead? Or am I just being paranoid? Any help appreciated with links to specific product(s). Either on aliexpress or for UK / ebay. Many thanks.