AMD Instinct MI100 vs AMD Radeon Pro W6600X Comparison

AMD’s Instinct MI100 and Radeon Pro W6600X are both end-of-life workstation accelerators, but they target entirely different corners of the professional market. The MI100 is a first-generation CDNA compute monster built for HPC and AI workloads, while the W6600X is a compact RDNA 2 card designed for Apple Mac Pro environments. The benchmark data shows a clear gulf in raw compute performance, but the W6600X brings architectural features and efficiency that the older MI100 lacks. This analysis breaks down where each card stands based strictly on recorded specifications and benchmark results.

Head-to-Head Benchmarks

The two cards do not share a common benchmark test in the data. The Instinct MI100 was tested with Geekbench OpenCL, scoring 139,035 points. The Radeon Pro W6600X was tested with Geekbench Metal, scoring 107,342 points. Because these are different APIs and different test suites, a direct cross-score comparison is not valid. However, each card’s position relative to its own nearest rivals tells a clear story.

The MI100’s OpenCL score of 139,035 places it in the 96th percentile of all GPUs. It sits 0.7% ahead of the NVIDIA Tesla V100 PCIe 16 GB (138,063) and 0.9% ahead of the Tesla V100 SXM2 32 GB (137,731). The lead grows to 1.9% over the AMD Radeon PRO V620 (136,472) and 2.4% over the AMD Radeon Pro W6800X Duo (135,774). These are narrow margins, but they show the MI100 consistently edges out some of the most respected compute accelerators of its generation. The data indicates a card that was at the top of the OpenCL heap when it launched.

The W6600X’s Metal score of 107,342 puts it in the 94th percentile of all GPUs. It is 0.6% ahead of the AMD Radeon Pro Vega II Duo (106,750) but trails the AMD Radeon Pro Vega II (109,617) by 2.1% and the AMD Radeon PRO W7900 (110,725) by 3.1%. It leads the NVIDIA Quadro RTX 6000 (101,872) by a more substantial 5.4%. So in the Metal ecosystem, the W6600X is a solid mid-pack performer, competitive with older Vega-era flagships but not a class leader. Its 94th percentile ranking is respectable, but two percentile points below the MI100.

The raw performance gap is stark when comparing specifications that drive compute throughput. The MI100 delivers 23.07 TFLOPS of FP32 and 46.14 TFLOPS of FP16, while the W6600X manages 10.15 TFLOPS FP32 and 20.31 TFLOPS FP16. That means the MI100 offers 2.27x the FP32 throughput and 2.27x the FP16 throughput. In texture rate, the MI100 hits 721.0 GTexel/s versus 317.3 GTexel/s for the W6600X. The MI100 also has a higher pixel rate of 96.13 GPixel/s versus 158.7 GPixel/s for the W6600X — here the W6600X actually wins by 65%.

FAQ

Q: Which card has more memory bandwidth?

A: The Instinct MI100. It has 32 GB of HBM2 on a 4096-bit bus, yielding 1.23 TB/s of bandwidth. The W6600X has 8 GB of GDDR6 on a 128-bit bus, yielding 256.0 GB/s. The MI100 provides 4.8x the bandwidth.

Q: Does the W6600X support ray tracing hardware?

A: Yes. The W6600X has 32 ray tracing cores. The MI100 has no dedicated ray tracing cores, as it is built on the CDNA 1.0 architecture which omits them.

Q: What is the power requirement difference?

A: The MI100 has a 300 W TDP and requires a 700 W suggested PSU with 2x 8-pin power connectors. The W6600X has a 120 W TDP and a 300 W suggested PSU, with no power connectors listed — it draws power through its Apple MPX bus interface.

Q: Which card is newer?

A: The W6600X was released on 2021-08-02, while the MI100 was released on 2020-11-15. The W6600X is roughly nine months newer.

Q: Do either of these cards have display outputs?

A: No. Both the MI100 and the W6600X list "No outputs" for display connectivity. They are compute-only or require a separate display adapter.

Q: What is the transistor density comparison?

A: The W6600X has a higher transistor density at 46.7M / mm², compared to the MI100’s 34.1M / mm². This is despite the MI100 having 25,600 million transistors versus 11,060 million for the W6600X.

The Verdict

The data points to a clear split. If the workload is OpenCL-heavy compute — think FP32/FP16 math, high-bandwidth memory access, or large dataset processing — the Instinct MI100 is the superior choice. Its 23.07 TFLOPS FP32 and 1.23 TB/s bandwidth are more than double the W6600X’s capabilities. The MI100’s 96th percentile ranking and its consistent lead over Tesla V100 variants confirm it as a high-end compute accelerator.

If the workload is Metal-based on a Mac Pro, or requires modern graphics features, the Radeon Pro W6600X is the only practical option. It supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, while the MI100 lists N/A for all three APIs. The W6600X also has ray tracing cores, which the MI100 lacks entirely. Its 94th percentile ranking shows it is no slouch, but it is clearly a lower-tier performer than the MI100 in raw compute.

Neither card is ideal for a general-purpose desktop. Both lack display outputs. The MI100 is end-of-life and was designed for server racks, while the W6600X is end-of-life and tied to the Apple MPX form factor. For pure compute density, pick the MI100. For compatibility with modern graphics APIs and Mac Pro integration, pick the W6600X.

Specification Differences

The two cards differ on nearly every measurable specification. The MI100 uses a 7 nm Arcturus chip with CDNA 1.0 architecture, while the W6600X uses a 7 nm Navi 23 chip with RDNA 2.0 architecture. Both are fabricated by TSMC, but the die sizes diverge: 750 mm² for the MI100 versus 237 mm² for the W6600X. Transistor counts are 25,600 million versus 11,060 million, with the W6600X having higher density at 46.7M / mm² versus 34.1M / mm².

Clock speeds favor the W6600X. Its base clock is 2068 MHz and boost is 2479 MHz, versus the MI100’s 1000 MHz base and 1502 MHz boost. Memory speed also differs: the W6600X runs at 2000 MHz (16 Gbps effective), while the MI100 runs at 1200 MHz (2.4 Gbps effective). The MI100 compensates with a 4096-bit bus and 32 GB HBM2, versus the W6600X’s 128-bit bus and 8 GB GDDR6.

Compute unit counts differ significantly. The MI100 has 7,680 shading units, 480 TMUs, and 64 ROPs. The W6600X has 2,048 shading units, 128 TMUs, and 64 ROPs. The MI100 has no ray tracing cores, while the W6600X has 32. The MI100’s TDP is 300 W with a 700 W suggested PSU, while the W6600X is 120 W with a 300 W suggested PSU. The bus interface is PCIe 4.0 x16 for the MI100 and Apple MPX for the W6600X.

Architecture Differences

The architectural gap is fundamental. The MI100 uses CDNA 1.0, AMD’s first dedicated compute architecture, which strips out graphics-specific features to maximize math throughput. The W6600X uses RDNA 2.0, a gaming-derived architecture that retains full graphics capabilities and adds ray tracing. This explains the API support disparity: the MI100 lists N/A for DirectX, OpenGL, and Vulkan, while the W6600X supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4.

The MI100’s compute focus is evident in its shading unit count — 7,680 units versus 2,048 for the W6600X — and its massive memory subsystem. The 4096-bit HBM2 bus is over 32x wider than the W6600X’s 128-bit GDDR6 bus. This is a design for bandwidth-hungry HPC workloads. The W6600X, by contrast, uses a smaller die with higher clock speeds and ray tracing cores, indicating a preference for graphics and rendering tasks.

The process node is the same (7 nm TSMC), but the transistor density differs. The W6600X packs 46.7M transistors per mm² versus 34.1M for the MI100, showing a more modern design methodology despite the larger absolute transistor count on the MI100. The MI100’s 750 mm² die is over 3x the size of the W6600X’s 237 mm² die, which explains its higher power draw and cooling requirements (dual-slot for both, but the MI100 needs 2x 8-pin connectors).

Where Each One Wins

The Instinct MI100 wins decisively in raw compute performance. It has 2.27x the FP32 throughput, 2.27x the FP16 throughput, 2.27x the texture rate, and 4.8x the memory bandwidth. It also has 3.75x the shading units and 3.75x the TMUs. For tasks like scientific simulation, machine learning training, or large-scale data processing, the MI100 is the clear winner. Its 96th percentile ranking and narrow lead over Tesla V100 cards reinforce this.

The Radeon Pro W6600X wins in efficiency and modern features. It has a 120 W TDP versus 300 W, meaning it draws less than half the power. It has ray tracing cores, which the MI100 lacks. It supports DirectX 12 Ultimate, OpenGL 4.6, and Vulkan 1.4, while the MI100 has no graphics API support. It also has a higher pixel rate (158.7 GPixel/s versus 96.13 GPixel/s) and higher clock speeds (2479 MHz boost versus 1502 MHz boost). For Mac Pro users running Metal workloads or for any task requiring modern graphics APIs, the W6600X is the only choice.

The data also shows the W6600X is more densely packed (46.7M transistors per mm²), indicating a more efficient design. Its 94th percentile ranking, while lower than the MI100’s 96th, is still strong for a card with a 120 W TDP. The MI100’s launch MSRP is not listed, while the W6600X had a launch MSRP of 699 USD. The MI100 has no display outputs and requires a 700 W PSU, making it a server-only part. The W6600X also has no display outputs but requires only a 300 W PSU and uses the Apple MPX interface, making it a drop-in card for compatible Mac Pro systems.