The Ryzen 3600XT, 3800XT and 3900XT has been launched by AMD for about a month. The gaming performance in certain games, when compared to the non-XT models, seemed to have improvements. The overclock abilities, thermal and wattage seems to suggest an improvement as well, as the XT models can perform at higher frequencies than the non-XT ones most of the time. However, with approximately $20 USD difference in price, the price-to-performance ratio seems not so promising. For instance, 3600XT is only $20 USD less than a 3700X, yet 3700X is known for its 8-core, 16 threads specification, which is much better performance in productivity when compared to a 6-core 3600XT.
In terms of gaming performance, the difference was no more than 10 % increase most of the time in all games, which means if you have a decent graphics card, you cannot really tell the difference in frame rate. Not to mention, in some of the games, the non-XT models even beated the newer XT models.
Although it is tempting to say wait for the 4000 series Ryzen, which the roadmap is not delayed by the COVID-19 drastically, we will not be getting any of them until 2021 (except OEMs). Therefore, my final advice for DIY PC builders this year is to get regular Ryzen CPU models, depending on your budget and demands. The Ryzen 3000 series ground-breaking Zen 2 Architecture with IPC improvement has made the CPU very much capable of all tasks such as gaming and editing. Since its launch, the sales has been constantly rising meanwhile Intel is struggling to upgrade their architecture.
Source: (GamerNexus) Review of 3600XT: https://www.youtube.com/watch?v=T7x6OvVU90A
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