Not sure why you'd want to buy a "new" RIVE anyhow ... it's X79, LGA1366 ... capable of running up to 64GB DDR3-1033 and i7-990X (6C/12T, 3.47GHz, 12MB L3) ... maybe capable of overclocking (with the best of the best parts) up to DDR4-2400 and up to ~4.4GHz... definitely a mighty beast circa 2011 and still a collectible enthusiast item ... but barely as fast and powerful as a mid-end modern system, not even comparable to a higher-end modern system.
More to the point, I wouldn't expect a motherboard or CPU more than twice as old as its warranty period to offer a whole lot more longevity, lol. Expect compatibility and stability issues when interfacing old tech with new tech, hardware and software, unless you're prepared to constantly tweak a lot of finicky quirks and settings.
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