Much like the first gen counterparts, the 2500X is a quad core processor with simultaneous multi-threading while the 2300X is a straight forward quad core. The X processors usually have a higher thermal design power (TDP) than hypothetical non-X equivalents, allowing them to take advantage of AMDs Extreme Frequency Range technology for higher turbos for longer given sufficient cooling, although these are set at 65W, similar to non-X processors.
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