The RX 6400 makes the most sense at entry-level settings, so we'll start with 1080p medium testing. You might be able to push some games to high or even ultra settings, but the GPU already struggled with a few of the games in our current test suite at medium.
The RX 6400 averaged 56 fps across the eight games we tested, just 3% faster than the old GTX 1650 GDDR5. It was also 21-23% slower than the RX 6500 XT, GTX 1650 Super, and RX 5500 XT 4GB, which were basically in a three-way tie at around 71–72 fps.
In the individual game charts, there's plenty of variability between the games. Total War: Warhammer 3 was by far the worst result, where the RX 6400 only managed 26 fps and came in 23% behind the GTX 1650. The best result was in Red Dead Redemption 2, where it was 15% faster than the 1650.
The main attraction is the card's size and power requirement, and the RX 6500 XT right now can be had for just $15 more (a 9% increase in GPU cost) while delivering 25–30% more performance. Yes, it needs a 6-pin power connector, but the vast majority of PCs should be able to manage that.
Cranking the settings to maximum presents a lot of difficulty for the RX 6400, even at 1080p. Multiple games exceed its 4GB VRAM, and the texture thrashing that occurs — where the GPU needs to pull data over the PCIe interface — gets hampered by the x4 connection. Basically, more demanding games will often fail to break 30 fps, and you'll generally want to use lower settings.
As a result of the above, the RX 6400 trailed the GTX 1650 by 11% at 1080p ultra. The RX 6500 XT also struggled, for the same reasons, so the performance gap was relatively consistent and remained at 24%. The RX 6400 was also 29% slower than the RX 5500 XT 4GB and GTX 1650 Super, and 40% slower than the RX 5500 XT 8GB that has enough VRAM to generally avoid memory thrashing.
Our ray tracing test suite really exists to test higher-end graphics cards, but since the RX 6400 has the requisite DirectX 12 Ultimate feature set, we gave it a shot. As with the 6500 XT, Control failed to run in DXR mode because it needs 6GB or more VRAM, but the rest of the games at least ran… or at least wobbled along drunkenly. And again, you don't need to enable ray tracing to enjoy a game, certainly not on a GPU like the RX 6400.
The RX 6500 XT maintained a 25% lead over the RX 6400, just as with our standard test suite. The DXR requirement means that most of the other competing GPUs are completely unable to run these tests, so the next closest GPU is the RTX 3050, which is a huge step up in performance. It was already over twice as fast at 1080p ultra without DXR, and now it's triple the performance — for a bit less than double the cost.
Don't feel too bad about the performance on tap. As bad as this might look compared to dedicated graphics cards, the RX 6400 should still deliver superior performance to any current integrated graphics solution. It has the same number of compute units (CUs) as the Ryzen 7 6800U, with a higher power limit and dedicated VRAM, plus 16MB of Infinity Cache. It will also be faster than the GPU in Apple's new M2, based on specs and features. Just remember to keep your expectations and settings in check.