AMD Instinct MI455X vs AMD Radeon RX 9050 Comparison

FAQ

Q: What are the core architectures of the AMD Instinct MI455X and the AMD Radeon RX 9050?

A: The AMD Instinct MI455X uses the CDNA 5.0 architecture with the MI450 256CU chip. The AMD Radeon RX 9050 uses the RDNA 4.0 architecture with the Navi 44 chip.

Q: How do the memory subsystems differ between these two cards?

A: The Instinct MI455X features 432 GB of HBM4 memory on a 24576-bit bus, delivering 23.3 TB/s bandwidth. The Radeon RX 9050 has 8 GB of GDDR6 memory on a 128-bit bus, delivering 288.0 GB/s bandwidth.

Q: What is the FP32 compute performance of each GPU?

A: The Instinct MI455X delivers 157.3 TFLOPS FP32, while the Radeon RX 9050 delivers 10.65 TFLOPS FP32. Both cards provide a 1:1 FP16 to FP32 ratio.

Q: What are the power requirements for each card?

A: The Instinct MI455X has a TDP of 2300 W and requires a suggested power supply of 2700 W. The Radeon RX 9050 has a TDP of 92 W and requires a suggested power supply of 250 W.

Q: What is the production status of each product?

A: The Radeon RX 9050 is marked as "Active" in production status. The production status for the Instinct MI455X is not recorded in the database.

Q: What display outputs does each card provide?

A: The Radeon RX 9050 provides 1x HDMI 2.1b and 2x DisplayPort 2.1a outputs. The Instinct MI455X provides no display outputs.

Where Each One Wins

The benchmark data splits these two GPUs along fundamentally different use cases. The AMD Instinct MI455X is a compute-oriented accelerator with a massive memory pool and extreme throughput, while the AMD Radeon RX 9050 is a conventional graphics card with display output and API support.

The Instinct MI455X wins decisively in raw compute workloads. Its FP32 throughput of 157.3 TFLOPS is roughly 14.8 times higher than the Radeon RX 9050's 10.65 TFLOPS. The texture rate of 2,457.6 GTexel/s on the MI455X dwarfs the 166.4 GTexel/s on the RX 9050, indicating a substantial advantage in texture-heavy compute tasks. Memory bandwidth is another clear win for the MI455X: 23.3 TB/s versus 288.0 GB/s, a difference of about 80.9 times. For workloads that require massive data movement, such as large-scale matrix operations or high-resolution scientific simulations, the MI455X is the clear choice based on the recorded measurements.

The Radeon RX 9050 wins in areas where the MI455X has no functional capability. It is the only one of the two with display outputs, providing 1x HDMI 2.1b and 2x DisplayPort 2.1a. It also supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, while the MI455X has no API support recorded. The RX 9050 also delivers a pixel rate of 166.4 GPixel/s, whereas the MI455X shows 0 MPixel/s, confirming that the Radeon card is designed for rasterization and rendering tasks. The RX 9050's power efficiency is also notable: its 92 W TDP is drastically lower than the MI455X's 2300 W, making it far more practical for conventional desktop and workstation environments.

The MI455X uses an EAM Module slot width and requires no power connectors, while the RX 9050 uses a Dual-slot design with a single 8-pin power connector. The MI455X operates on PCIe 6.0 x16, while the RX 9050 uses PCIe 5.0 x16.

Architecture Differences

The two GPUs represent divergent architectural philosophies from AMD. The Instinct MI455X is built on CDNA 5.0, a compute-focused architecture, while the Radeon RX 9050 uses RDNA 4.0, a graphics-focused architecture. These are not incremental variations; they are entirely different design families with different chip configurations.

The MI455X uses the MI450 256CU chip, which contains 320,000 million transistors on a 2 nm process from TSMC. The die size is 2990 mm², yielding a transistor density of 107.0M per mm². The RX 9050 uses the Navi 44 chip, which contains 29,700 million transistors on a 4 nm process from TSMC. Its die size is 199 mm², yielding a higher transistor density of 149.2M per mm². The smaller process node on the MI455X does not translate to higher density because the chip is substantially larger and more complex.

The shading unit counts differ enormously: the MI455X has 32,768 shading units, while the RX 9050 has 1,024. The MI455X has 1,024 texture mapping units, while the RX 9050 has 64. The ROP counts also differ: the MI455X has 0 ROPs, while the RX 9050 has 64. The MI455X does not have RT cores recorded, while the RX 9050 has 16 RT cores. Neither card has tensor cores listed in the database.

Memory architecture is a fundamental differentiator. The MI455X uses HBM4 memory with 432 GB capacity and a 24576-bit bus. The RX 9050 uses GDDR6 memory with 8 GB capacity and a 128-bit bus. This explains the massive bandwidth gap: 23.3 TB/s versus 288.0 GB/s. The MI455X's memory clock is listed as 1900 MHz with 7.6 Gbps effective, while the RX 9050's memory clock is 2250 MHz with 18 Gbps effective.

Clock speeds also reflect different design targets. The MI455X has a base clock of 1000 MHz and a boost clock of 2400 MHz. The RX 9050 has a base clock of 1330 MHz, a boost clock of 2600 MHz, and a game clock of 1920 MHz. The RX 9050's higher base clock suggests it is optimized for sustained gaming and graphics workloads, while the MI455X relies on its massive parallel resources rather than raw clock speed.

Specification Differences

The recorded specifications show these key differences between the two cards:

• Chip: MI450 256CU versus Navi 44
• Architecture: CDNA 5.0 versus RDNA 4.0
• Generation: Instinct (MIx) versus Navi IV (RX 9000)
• Process node: 2 nm versus 4 nm
• Transistors: 320,000 million versus 29,700 million
• Die size: 2990 mm² versus 199 mm²
• Transistor density: 107.0M per mm² versus 149.2M per mm²
• Base clock: 1000 MHz versus 1330 MHz
• Boost clock: 2400 MHz versus 2600 MHz
• Game clock: not applicable versus 1920 MHz
• Memory clock: 1900 MHz 7.6 Gbps effective versus 2250 MHz 18 Gbps effective
• Memory size: 432 GB versus 8 GB
• Memory type: HBM4 versus GDDR6
• Memory bus width: 24576 bit versus 128 bit
• Memory bandwidth: 23.3 TB/s versus 288.0 GB/s
• Shading units: 32,768 versus 1,024
• TMUs: 1,024 versus 64
• ROPs: 0 versus 64
• RT cores: not recorded versus 16
• Pixel rate: 0 MPixel/s versus 166.4 GPixel/s
• Texture rate: 2,457.6 GTexel/s versus 166.4 GTexel/s
• FP32: 157.3 TFLOPS versus 10.65 TFLOPS
• FP16: 157.3 TFLOPS (1:1) versus 10.65 TFLOPS (1:1)
• TDP: 2300 W versus 92 W
• Slot width: EAM Module versus Dual-slot
• Power connectors: None versus 1x 8-pin
• Suggested PSU: 2700 W versus 250 W
• Bus interface: PCIe 6.0 x16 versus PCIe 5.0 x16
• Display outputs: No outputs versus 1x HDMI 2.1b, 2x DisplayPort 2.1a
• DirectX support: N/A versus 12 Ultimate (12_2)
• OpenGL support: N/A versus 4.6
• Vulkan support: N/A versus 1.4
• Release date: 2026-07-22 versus 2026-07-27
• Predecessor: Radeon Instinct versus Navi III

Head-to-Head Benchmarks

The head-to-head benchmark array is empty, so the comparison relies on the recorded specification data. The largest wins for the Instinct MI455X come in raw computational throughput and memory bandwidth.

FP32 compute shows the MI455X at 157.3 TFLOPS versus the RX 9050 at 10.65 TFLOPS. The MI455X delivers approximately 14.8 times the FP32 performance. FP16 performance follows the same pattern, with both cards at 1:1 ratios, so the MI455X again delivers 157.3 TFLOPS versus 10.65 TFLOPS.

Texture rate demonstrates another dominant win for the MI455X. At 2,457.6 GTexel/s versus 166.4 GTexel/s, the MI455X provides roughly 14.8 times the texture processing throughput. This directly reflects the large difference in TMU counts: 1,024 versus 64.

Memory bandwidth shows the most extreme gap. The MI455X delivers 23.3 TB/s, which is approximately 80.9 times the RX 9050's 288.0 GB/s. This is enabled by the HBM4 memory type, 432 GB capacity, and 24576-bit bus width, all of which are far beyond the GDDR6 configuration on the RX 9050.

The Radeon RX 9050 wins in pixel throughput. It records 166.4 GPixel/s, while the MI455X records 0 MPixel/s. This is consistent with the MI455X having 0 ROPs and no display outputs, indicating it is not designed for rasterized graphics output.

Clock speeds favor the RX 9050. Its base clock of 1330 MHz exceeds the MI455X's 1000 MHz base clock. Its boost clock of 2600 MHz exceeds the MI455X's 2400 MHz boost clock. The RX 9050 also has a game clock of 1920 MHz, a specification not present on the MI455X.

Transistor density favors the RX 9050 as well. At 149.2M per mm², it packs transistors more densely than the MI455X's 107.0M per mm², despite using an older 4 nm process. This indicates a more compact and efficient design layout on the Navi 44 chip.

Power consumption shows a stark contrast. The MI455X requires 2300 W TDP and a 2700 W suggested PSU, while the RX 9050 operates at 92 W TDP with a 250 W suggested PSU. The RX 9050 uses about 4 percent of the power of the MI455X while delivering roughly 6.8 percent of the FP32 throughput.

The release dates are close, with the MI455X recorded as 2026-07-22 and the RX 9050 as 2026-07-27. Both cards have a percentile ranking of 50 against all GPUs in the database, and both have an average benchmark score of 0, reflecting the absence of recorded benchmark results. The nearest rivals lists are empty for both products.

The MI455X is a compute accelerator with no graphics capabilities: no display outputs, no API support, no pixel rate. The RX 9050 is a complete graphics solution with modern API support, display connectivity, and rasterization hardware. The data indicates two products designed for entirely separate segments of the GPU market, with the MI455X optimized for data-center compute and the RX 9050 for conventional graphics rendering.