AMD Instinct MI455X vs AMD Radeon PRO W7700 Comparison

The Verdict

The AMD Instinct MI455X and AMD Radeon PRO W7700 serve entirely different purposes, and the database shows almost no overlap in their intended workloads. The MI455X is a 2 nm CDNA 5.0 accelerator with 432 GB of HBM4 memory, a 24576-bit bus, and 23.3 TB/s of bandwidth. It targets massive compute tasks where memory capacity and throughput matter more than display output. The Radeon PRO W7700 is a 5 nm RDNA 3.0 workstation card with 16 GB of GDDR6, 576.0 GB/s of bandwidth, and four DisplayPort 2.1 outputs. It targets professional visualization and rendering workloads that require rasterization and graphics APIs.

The MI455X has no display outputs, no DirectX support, no OpenGL support, and no Vulkan support. The W7700 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. Anyone needing to drive monitors should choose the W7700. Anyone needing raw compute throughput and enormous memory capacity should choose the MI455X. The MI455X has 32768 shading units versus 3072 on the W7700, and its FP32 throughput of 157.3 TFLOPS is roughly five times the W7700's 31.95 TFLOPS. The MI455X also has a 2300 W TDP versus 190 W for the W7700, indicating vastly different power delivery requirements.

The W7700 holds benchmark data in the database: a Geekbench OpenCL score of 108245 and a Geekbench Vulkan score of 129706. Its average benchmark score is 118976, placing it at the 95th percentile among all GPUs. The MI455X has no recorded benchmark scores and sits at the 50th percentile with an average score of zero. The MI455X is designed for a different class of workload, one where standard graphics benchmarks do not apply. The data indicates that the W7700 is the only one of the two that can be evaluated through conventional GPU benchmarking.

Where Each One Wins

The MI455X wins on raw compute resources. Its 32768 shading units, 1024 texture mapping units, and 157.3 TFLOPS FP32 performance dwarf the W7700's 3072 shading units, 192 texture mapping units, and 31.95 TFLOPS. The MI455X also delivers 157.3 TFLOPS FP16 at a 1:1 ratio, while the W7700 delivers 63.90 TFLOPS FP16 at a 2:1 ratio. The MI455X texture rate is 2,457.6 GTexel/s compared to 499.2 GTexel/s on the W7700. The MI455X has a pixel rate of 0 MPixel/s because it has no ROPs, while the W7700 has 96 ROPs and a 249.6 GPixel/s pixel rate. The MI455X is a compute accelerator, not a rasterizer.

The W7700 wins on graphics capability and practical workstation use. It has 48 ray tracing cores, while the MI455X lists no ray tracing cores. The W7700 supports modern graphics APIs, has four DisplayPort 2.1 outputs, and uses a standard PCIe 4.0 x16 interface with a dual-slot form factor and one 8-pin power connector. The MI455X uses an EAM Module slot width, has no power connectors listed, and requires a suggested PSU of 2700 W. The W7700 requires a suggested PSU of 450 W.

The W7700 also wins on availability of measured performance data. Its Geekbench Vulkan score of 129706 exceeds its Geekbench OpenCL score of 108245 by roughly 20 percent. The nearest rivals in the database show the W7700's average score of 118976 is 1.3 percent ahead of the NVIDIA GB10 at 117393, 1.6 percent ahead of the NVIDIA RTX 4000 SFF Ada Generation at 117088, 4 percent ahead of the NVIDIA Tesla V100 SXM2 16 GB at 114395, and 4.4 percent ahead of the NVIDIA RTX A5500 Mobile at 113944. These deltas are modest, indicating the W7700 sits in a competitive performance band among professional workstation GPUs.

Architecture Differences

The MI455X uses the MI450 256CU chip built on a 2 nm process at TSMC. It packs 320,000 million transistors on a 2990 mm² die, yielding a transistor density of 107.0M per mm². The architecture is CDNA 5.0, AMD's compute-focused design. The W7700 uses the Navi 32 chip built on a 5 nm process at TSMC. It has 28,100 million transistors on a 346 mm² die, yielding a transistor density of 81.2M per mm². The architecture is RDNA 3.0 with the codename "Wheat Nas." The MI455X generation is listed as "Instinct (MIx)" while the W7700 generation is "Radeon Pro Navi (Navi III Series)."

Memory architecture differs fundamentally. The MI455X uses HBM4 with 432 GB capacity, a 24576-bit bus, and 23.3 TB/s bandwidth. The W7700 uses GDDR6 with 16 GB capacity, a 256-bit bus, and 576.0 GB/s bandwidth. The MI455X memory clock is 1900 MHz at 7.6 Gbps effective, while the W7700 memory clock is 2250 MHz at 18 Gbps effective. Despite the W7700's higher memory clock, the MI455X's enormous bus width gives it roughly 40 times the memory bandwidth.

Clock speeds also differ. The MI455X base clock is 1000 MHz with a boost of 2400 MHz. The W7700 base clock is 1900 MHz with a boost of 2600 MHz. The W7700 runs at higher clocks, but the MI455X compensates with far more compute units and shading units. The MI455X has no ROPs, no display outputs, and no graphics API support. The W7700 has 96 ROPs, four DisplayPort 2.1 outputs, and full DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4 support. The MI455X uses PCIe 6.0 x16 while the W7700 uses PCIe 4.0 x16. The MI455X release date is 2026-07-22, while the W7700 released on 2023-11-12. The W7700 has a launch MSRP of 999 USD.

FAQ

Q: Which card has more memory bandwidth?

A: The MI455X has 23.3 TB/s bandwidth from its HBM4 memory on a 24576-bit bus. The W7700 has 576.0 GB/s bandwidth from its GDDR6 memory on a 256-bit bus.

Q: Can the MI455X output video to displays?

A: No. The MI455X lists no display outputs, while the W7700 has four DisplayPort 2.1 outputs.

Q: How do the FP32 performance figures compare?

A: The MI455X delivers 157.3 TFLOPS FP32, while the W7700 delivers 31.95 TFLOPS FP32.

Q: What is the W7700's benchmark position relative to its nearest rivals?

A: The W7700's average benchmark score of 118976 is 1.3 percent ahead of the NVIDIA GB10, 1.6 percent ahead of the NVIDIA RTX 4000 SFF Ada Generation, 4 percent ahead of the NVIDIA Tesla V100 SXM2 16 GB, and 4.4 percent ahead of the NVIDIA RTX A5500 Mobile.

Q: Which card supports ray tracing?

A: The W7700 has 48 ray tracing cores. The MI455X lists no ray tracing cores.

Q: What are the power requirements for each card?

A: The MI455X has a 2300 W TDP and a suggested PSU of 2700 W. The W7700 has a 190 W TDP and a suggested PSU of 450 W.

Head-to-Head Benchmarks

The database contains no direct head-to-head benchmark results between the MI455X and the W7700. The MI455X has no benchmark entries at all, while the W7700 has two recorded scores. The W7700's Geekbench OpenCL score is 108245 and its Geekbench Vulkan score is 129706. The MI455X's average benchmark score is zero because no benchmarks are recorded. This absence of data reflects the fundamental difference in purpose: the MI455X is a compute accelerator that does not run standard graphics benchmarks, while the W7700 is a workstation GPU designed for those tests.

The W7700's performance against its nearest rivals is measurable. Its average score of 118976 puts it ahead of the NVIDIA GB10 by 1.3 percent, ahead of the NVIDIA RTX 4000 SFF Ada Generation by 1.6 percent, ahead of the NVIDIA Tesla V100 SXM2 16 GB by 4 percent, and ahead of the NVIDIA RTX A5500 Mobile by 4.4 percent. These are small margins, indicating the W7700 is competitive but not dominant within its peer group. The Vulkan score of 129706 is notably higher than the OpenCL score of 108245, suggesting the W7700's graphics-oriented architecture performs better under Vulkan workloads.

For the MI455X, the only quantitative comparison comes from architectural specifications. Its FP32 throughput of 157.3 TFLOPS is roughly 4.9 times the W7700's 31.95 TFLOPS. Its texture rate of 2,457.6 GTexel/s is roughly 4.9 times the W7700's 499.2 GTexel/s. Its memory bandwidth of 23.3 TB/s is roughly 40 times the W7700's 576.0 GB/s. Its memory capacity of 432 GB is 27 times the W7700's 16 GB. These ratios indicate the MI455X is designed for workloads that the W7700 cannot approach, such as large-scale AI training or scientific simulation where memory capacity and bandwidth are the limiting factors.

The W7700 counters with features the MI455X lacks entirely: 96 ROPs, 249.6 GPixel/s pixel rate, 48 ray tracing cores, and full graphics API support. The MI455X has zero ROPs and a zero pixel rate. The W7700 also has a higher boost clock at 2600 MHz versus 2400 MHz, and a higher base clock at 1900 MHz versus 1000 MHz. The W7700's transistor density is lower at 81.2M per mm² versus 107.0M per mm², but its 5 nm process and smaller die of 346 mm² make it far more practical for standard workstation builds. The MI455X's 2990 mm² die and 2300 W TDP place it in an entirely different hardware class.

Specification Differences

The two cards differ across nearly every recorded specification. The MI455X uses a 2 nm process, the W7700 uses 5 nm. The MI455X has 320,000 million transistors, the W7700 has 28,100 million. The MI455X die size is 2990 mm², the W7700 is 346 mm². The MI455X transistor density is 107.0M per mm², the W7700 is 81.2M per mm². The MI455X base clock is 1000 MHz, the W7700 is 1900 MHz. The MI455X boost clock is 2400 MHz, the W7700 is 2600 MHz. The MI455X memory clock is 1900 MHz at 7.6 Gbps effective, the W7700 is 2250 MHz at 18 Gbps effective.

Memory specifications diverge completely. The MI455X has 432 GB of HBM4, the W7700 has 16 GB of GDDR6. The MI455X bus width is 24576 bit, the W7700 is 256 bit. The MI455X bandwidth is 23.3 TB/s, the W7700 is 576.0 GB/s. The MI455X has 32768 shading units, the W7700 has 3072. The MI455X has 1024 TMUs, the W7700 has 192. The MI455X has 0 ROPs, the W7700 has 96. The W7700 has 48 ray tracing cores, the MI455X has none. The MI455X pixel rate is 0 MPixel/s, the W7700 is 249.6 GPixel/s. The MI455X texture rate is 2,457.6 GTexel/s, the W7700 is 499.2 GTexel/s.

FP32 performance is 157.3 TFLOPS for the MI455X versus 31.95 TFLOPS for the W7700. FP16 performance is 157.3 TFLOPS at 1:1 for the MI455X versus 63.90 TFLOPS at 2:1 for the W7700. TDP is 2300 W versus 190 W. Slot width is EAM Module versus dual-slot. Power connectors are none versus one 8-pin. Suggested PSU is 2700 W versus 450 W. Bus interface is PCIe 6.0 x16 versus PCIe 4.0 x16. Display outputs are none versus four DisplayPort 2.1. DirectX support is N/A versus 12 Ultimate (12_2). OpenGL support is N/A versus 4.6. Vulkan support is N/A versus 1.4. The W7700 dimensions are 241 mm by 111 mm, the MI455X has no recorded dimensions. Release dates are 2026-07-22 for the MI455X and 2023-11-12 for the W7700. The W7700 has a launch MSRP of 999 USD, while the MI455X has no recorded launch MSRP.