Ryzen 7 3800X vs Core i9-9900K

Gaming speed, cores and clocks

The Ryzen 7 3800X and the Core i9-9900K are within a few percent of each other for gaming. In a game, you will not see the difference.

The Ryzen 7 3800X has 8 cores and 16 threads, and the Core i9-9900K has 8 cores and 16 threads. Core counts are the same, so cache size and clock speed decide the difference. Boost clocks are 4.5 GHz and 5 GHz.

Platform, power and price

The Ryzen 7 3800X uses the AM4 socket and the Core i9-9900K uses LGA1151, so they need different motherboards, and often different memory. When you compare prices, count the board as well as the chip.

Rated power is 105 W for the first and 95 W for the second. That is close enough that cooling needs will be similar.

At launch the Ryzen 7 3800X cost $399 and the Core i9-9900K $488, which gives 13.0 and 10.5 points of gaming performance per $100. Today's prices will differ.

Which graphics cards each one can feed, and which to buy

At 1080p the Ryzen 7 3800X can feed a card up to the Radeon RX 6800 XT before it holds the card back by more than 10 percent. The Core i9-9900K reaches the GeForce RTX 4080 Laptop. Both chips are in the same range for graphics card pairing.

Choose the Ryzen 7 3800X if you want the faster gaming chip and the same or more cores. Choose the Core i9-9900K if you would rather spend the difference on a graphics card, which does more for frame rates in most games.