AMD Radeon RX 6400 vs AMD Radeon Vega 8 Mobile Comparison

Where Each One Wins

The benchmark data presents an unusually one-sided comparison. Across the two directly comparable workload tests in the database, the AMD Radeon RX 6400 claims victory in both. The Vega 8 Mobile records zero wins in the head-to-head tests, while the RX 6400 takes both. This is not a close contest by any measure, and the margin of victory in each test is substantial.

The AMD Radeon Vega 8 Mobile is an integrated graphics processor built into a mobile chip. Its performance profile is defined by its role as an IGP, with system-shared memory and a modest 25 W power envelope. The data shows it produces an average benchmark score of 7203 across all recorded tests, placing it in the 39th percentile of all GPUs in the database. Its nearest rivals in the aggregate rankings include the NVIDIA GeForce GTX 750, which scores an average of 7222, a difference of 0.3 percent in favor of the GTX 750. The Vega 8 Mobile also sits within 0.4 percent of the GeForce GTX 560 SE and within 0.5 percent of the Intel Iris Pro Graphics P580. These tight margins indicate that the Vega 8 Mobile occupies a specific performance tier, one populated by older discrete graphics cards and high-end integrated solutions.

The AMD Radeon RX 6400, by contrast, is a discrete graphics card from the Radeon RX 6000 series. It carries a dedicated 4 GB of GDDR6 memory on a 64-bit bus, and its power envelope is 53 W. The average benchmark score for the RX 6400 is 6001, placing it in the 35th percentile of all GPUs. Its nearest rivals are the NVIDIA GeForce GTX 770M at an average score of 6000, a 0 percent difference, and the NVIDIA RTX PRO 6000 Blackwell Server at 5996, a 0.1 percent difference. The RX 6400 also sits 0.2 percent ahead of the AMD FirePro W4100 and 0.3 percent ahead of the NVIDIA Quadro K4000M.

The apparent paradox here is worth investigating. The RX 6400 has the lower average benchmark score and the lower percentile ranking, yet it wins every head-to-head test against the Vega 8 Mobile by a wide margin. This discrepancy stems from the fact that the two GPUs were tested across different sets of workloads. The Vega 8 Mobile has only two recorded benchmark results, both from Geekbench. The RX 6400 has ten recorded results, including Passmark tests across multiple DirectX versions, a 3DMark test, and Geekbench tests. The broader test suite for the RX 6400 pulls its average down, while the Vega 8 Mobile's narrower set of tests keeps its average relatively higher. When the two are compared directly on the same workloads, the RX 6400 is decisively faster.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The AMD Radeon Vega 8 Mobile has an average benchmark score of 7203, while the AMD Radeon RX 6400 has an average benchmark score of 6001. This puts the Vega 8 Mobile in the 39th percentile of all GPUs and the RX 6400 in the 35th percentile.

Q: How does the Vega 8 Mobile compare to its nearest rivals?

A: The Vega 8 Mobile is essentially tied with the NVIDIA GeForce GTX 750, trailing by only 0.3 percent. It leads the GeForce GTX 560 SE by 0.4 percent and the Intel Iris Pro Graphics P580 by 0.5 percent.

Q: What is the RX 6400's closest rival in the database?

A: The RX 6400's nearest rival is the NVIDIA GeForce GTX 770M, with a 0 percent difference in average score. The NVIDIA RTX PRO 6000 Blackwell Server is 0.1 percent behind, and the AMD FirePro W4100 is 0.2 percent behind.

Q: Which GPU wins in Geekbench OpenCL performance?

A: The RX 6400 scores 32011 in Geekbench OpenCL, compared to 7435 for the Vega 8 Mobile. The RX 6400 leads by 76.8 percent in this test.

Q: Which GPU wins in Geekbench Vulkan performance?

A: The RX 6400 scores 16372 in Geekbench Vulkan, while the Vega 8 Mobile scores 6970. The RX 6400 leads by 57.4 percent in this test.

Q: What is the release timeline for these two GPUs?

A: The Vega 8 Mobile was released on January 7, 2019, and the RX 6400 was released on January 18, 2022. Both are now marked as end-of-life in the database.

Head-to-Head Benchmarks

The head-to-head results show a dominant performance from the RX 6400. In the Geekbench OpenCL test, the RX 6400 scores 32011 against the Vega 8 Mobile's 7435. The delta of 76.8 percent is the largest margin recorded between these two GPUs. This test is heavily compute-oriented, and the RX 6400's dedicated memory subsystem and higher shading unit count contribute to its advantage. The Vega 8 Mobile's system-shared memory and lower clock speeds hold it back significantly in this workload.

The Geekbench Vulkan test narrows the gap somewhat, but the RX 6400 still wins comfortably. The RX 6400 scores 16372, while the Vega 8 Mobile scores 6970. The delta is 57.4 percent in favor of the RX 6400. Vulkan is a lower-level API that can sometimes benefit integrated GPUs due to reduced driver overhead, but the raw hardware advantage of the RX 6400 remains decisive. The RX 6400's boost clock of 2321 MHz, compared to the Vega 8 Mobile's boost clock of 1101 MHz, is a major factor in this result.

The RX 6400 also has a much higher pixel rate of 74.27 GPixel/s, compared to the Vega 8 Mobile's 8.808 GPixel/s. Its texture rate of 111.4 GTexel/s dwarfs the Vega 8 Mobile's 35.23 GTexel/s. Floating-point performance follows the same pattern, with the RX 6400 delivering 3.565 TFLOPS of FP32 compute against the Vega 8 Mobile's 1,127.4 GFLOPS. These specifications align with the benchmark results, confirming that the RX 6400 is in a different performance class.

The Vega 8 Mobile does have one advantage in the recorded data: its average benchmark score across all tests is higher. This is a statistical artifact of the test selection rather than a reflection of real-world performance. The Vega 8 Mobile was only tested in two Geekbench workloads, both of which it loses decisively. The RX 6400 was subjected to a much wider variety of tests, including several Passmark DirectX tests where scores are not directly comparable to Geekbench results. When the same workload is run on both GPUs, the RX 6400 wins every time.

Specification Differences

The two GPUs differ in nearly every major specification category. The Vega 8 Mobile is built on a 14 nm process at GlobalFoundries, while the RX 6400 uses a 6 nm process at TSMC. The transistor counts are similar in magnitude, with the Vega 8 Mobile featuring 4,940 million transistors and the RX 6400 featuring 5,400 million. However, the die sizes are very different: the Vega 8 Mobile has a die size of 210 mm², while the RX 6400 has a die size of 107 mm². This translates to a transistor density of 23.5 million transistors per square millimeter for the Vega 8 Mobile and 50.5 million per square millimeter for the RX 6400.

Clock speeds show a substantial gap. The Vega 8 Mobile has a base clock of 300 MHz and a boost clock of 1101 MHz. The RX 6400 has a base clock of 1923 MHz, a game clock of 2039 MHz, and a boost clock of 2321 MHz. The RX 6400's memory runs at 2000 MHz with 16 Gbps effective speed, while the Vega 8 Mobile relies on system-shared memory with bandwidth described as system dependent.

Memory configuration is a fundamental difference. The Vega 8 Mobile has no dedicated VRAM, using system shared memory for both size and type. The RX 6400 has 4 GB of GDDR6 memory on a 64-bit bus, delivering 128.0 GB/s of bandwidth. The shading unit count also differs, with the Vega 8 Mobile featuring 512 shading units and the RX 6400 featuring 768 shading units. Texture mapping units number 32 on the Vega 8 Mobile versus 48 on the RX 6400. Render output units are 8 on the Vega 8 Mobile versus 32 on the RX 6400.

Power consumption is another clear differentiator. The Vega 8 Mobile has a TDP of 25 W and is classified as an IGP with no power connectors. The RX 6400 has a TDP of 53 W, is a single-slot card, and also requires no power connectors, though it does have a suggested PSU of 250 W. The bus interface differs as well, with the Vega 8 Mobile using an IGP interface and the RX 6400 using PCIe 4.0 x4. Display outputs on the RX 6400 include 1x HDMI 2.1 and 1x DisplayPort 1.4a, while the Vega 8 Mobile's outputs are described as portable device dependent.

Architecture Differences

The architectural divide between these two GPUs is generational. The Vega 8 Mobile is based on GCN 5.0, using the Raven-M chip and belonging to the Vega IGP generation from Raven Ridge-M. The RX 6400 is based on RDNA 2.0, using the Navi 24 chip and belonging to the Navi II generation from the RX 6000 series. This is a shift from one major architecture family to a completely different one, not merely a refinement of the same design.

The Vega 8 Mobile supports DirectX 12 (12_1), OpenGL 4.6, and Vulkan 1.3. The RX 6400 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The RX 6400 also includes 12 ray tracing cores, a feature entirely absent from the Vega 8 Mobile. This makes the RX 6400 capable of hardware-accelerated ray tracing, whereas the Vega 8 Mobile has no such capability.

The compute characteristics reflect the architectural changes. The Vega 8 Mobile's FP32 performance is 1,127.4 GFLOPS, and its FP16 performance is 2.255 TFLOPS at a 2:1 ratio. The RX 6400's FP32 performance is 3.565 TFLOPS, and its FP16 performance is 7.130 TFLOPS at a 2:1 ratio. The RX 6400's pixel rate of 74.27 GPixel/s and texture rate of 111.4 GTexel/s are both far higher than the Vega 8 Mobile's corresponding figures of 8.808 GPixel/s and 35.23 GTexel/s.

The production status for both is end-of-life, but their release dates are separated by roughly three years. The Vega 8 Mobile launched on January 7, 2019, succeeding GCN 3.0 IGP and preceding Navi II IGP. The RX 6400 launched on January 18, 2022, succeeding Navi and preceding Navi III. The RX 6400 has a recorded launch MSRP of 159 USD, while the Vega 8 Mobile has no recorded launch MSRP, consistent with its status as an integrated processor component.

The Verdict

The data points to a clear conclusion: the AMD Radeon RX 6400 is the faster GPU in every directly comparable workload. Its wins in both Geekbench OpenCL and Geekbench Vulkan are decisive, with margins of 76.8 percent and 57.4 percent respectively. The RX 6400 also holds advantages in raw specifications, including higher clock speeds, more shading units, dedicated GDDR6 memory, and support for ray tracing. For users who need discrete GPU performance, the RX 6400 is the obvious choice based on the recorded measurements.

The AMD Radeon Vega 8 Mobile, however, is not without its place. Its 25 W power envelope and integrated design make it suitable for portable devices where space and power are constrained. Its average benchmark score of 7203 is higher than the RX 6400's 6001, though this is due to the different test sets applied to each GPU. The Vega 8 Mobile's performance tier, as indicated by its nearest rivals, places it alongside the NVIDIA GeForce GTX 750 and the Intel Iris Pro Graphics P580. For systems that cannot accommodate a discrete card, the Vega 8 Mobile provides a baseline level of graphics capability.

The RX 6400's nearest rivals tell a different story. It sits alongside the NVIDIA GeForce GTX 770M and the AMD FirePro W4100, with all of these GPUs clustered within a 0.3 percent range of average score. This places the RX 6400 in a performance tier that is well above the Vega 8 Mobile in head-to-head comparisons, even though their aggregate averages differ.

The architecture differences reinforce the benchmark results. The RX 6400's RDNA 2.0 design, 6 nm process, and dedicated memory are all factors that contribute to its superior performance in the recorded tests. The Vega 8 Mobile's GCN 5.0 architecture and 14 nm process are older designs that cannot match the newer GPU in compute-heavy workloads.

The final recommendation follows the data. Users seeking maximum performance in the tested workloads should choose the AMD Radeon RX 6400. Its higher scores, dedicated memory, and modern feature set make it the stronger option. Users constrained by power, space, or system integration requirements may find the AMD Radeon Vega 8 Mobile acceptable, but the benchmark results indicate that it will deliver significantly lower performance in OpenCL and Vulkan workloads. The RX 6400 is the winner in this comparison, and the recorded data does not suggest any scenario where the Vega 8 Mobile outperforms it in the tests they share.