These CPUs were introduced last month, and even then it was clear that they hardly have any special meaning. To begin with about the characteristics, and at the same time we mention the “ordinary” models so that you can see the difference.
As you can see, it is almost nonexistent. An increase of 100-200 MHz to the peak frequencies, which are not always achieved, will obviously not lead to any significant increase in performance. Actually, even AMD itself provides such a diagram.
Now let's move on to the real tests. There are a huge number of them on the Web today, but I will give only a few – the situation is clear and so.
Yes, the average growth is only 2-3%, and in some applications it is at the level of error. Power consumption and temperature have changed about the same.
Why are these CPUs needed? If we focus on the recommended prices, they are identical for the new models to the old ones. That is, the Ryzen 9 3900XT costs the same as the Ryzen 9 3900X. But these are the recommended prices. Let me remind you that the Ryzen 9 3900X, along with the rest of the lineup models, appeared last summer, which means that it managed to get pretty cheaper. Not all models have fallen in price the same way, but, for example, the Ryzen 9 3900X in the USA now costs not at all 500 dollars, but 430 dollars. That is, at the moment, it makes no sense to buy updated CPUs.
But AMD did not release them at all in order to really make its line better. It was just necessary to answer the recently released Intel Comet Lake-S line of processors, so it’s all about marketing. In addition, not all PC buyers are versed in hardware, but here are supposedly new CPUs that came out even later than competing Intel solutions. Well, do not forget about the finished PC market, which is very large.
In general, if you are going to buy an AMD processor, you can’t look at the XT models yet – take something from the main line or wait for the new generation, which will be presented, presumably, in October.