Based on the Phoronix tests I've seen, AMD EPYC or AMD Threadripper is better for cost / performance.
But Xeon Phi is an accelerator over PCIe. Its more comparable to a NVidia Tesla V100. You write specialized software to run on the Xeon Phi (even though it shares the x86 instruction set, its architecture is alien so it requires the programmer to specifically optimize for the Phi platform).
Based on the Phoronix tests I've seen, AMD EPYC or AMD Threadripper is better for cost / performance.
But Xeon Phi is an accelerator over PCIe. Its more comparable to a NVidia Tesla V100. You write specialized software to run on the Xeon Phi (even though it shares the x86 instruction set, its architecture is alien so it requires the programmer to specifically optimize for the Phi platform).