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Realtek's $10 tiny 10GbE network adapter is coming to motherboards later this year
(www.tomshardware.com)
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A lot of those modules would work fine if the companies didn't fuck with their drivers.
The Linux ixgbe driver (for Intel 82598 and 82599 chipsets) was submitted with a whitelist for Intel SFP+ adapters. Linux devs added a module option to shut off the whitelist, and tons of stuff is perfectly compatible.