AMD Radeon 840M vs AMD Radeon PRO W7900D Comparison

The Verdict

The data in this comparison is unambiguous. The AMD Radeon PRO W7900D is a discrete workstation graphics card built on the Navi 31 chip with RDNA 3.0 architecture, while the AMD Radeon 840M is an integrated graphics processor (IGP) on the Krackan Point chip with RDNA 3.5 architecture. The W7900D delivers 52.99 TFLOPS of FP32 performance, a 34.7 times higher figure than the 840M's 1,484.8 GFLOPS. This massive gap translates into the W7900D being the only choice for compute-heavy professional workloads, 3D rendering, and any task that requires sustained high throughput. The 840M, with its 15 W TDP and system-shared memory, is positioned for basic display output and light GPU acceleration in thin-and-light laptops. The recorded data shows no benchmark scores for either product, so direct performance percentages cannot be stated, but the raw specifications alone define their distinct roles. Users who need a professional-grade card for simulation, AI inference, or large-scale visualizations should select the W7900D. Users who require a low-power integrated solution for a portable device should select the 840M. There is no overlap in their intended usage.

Where Each One Wins

The AMD Radeon PRO W7900D wins in every category that involves raw processing power. Its 6,144 shading units, 384 texture mapping units, and 192 render output units dwarf the 840M's 256 shading units, 16 TMUs, and 8 ROPs. The W7900D also has 96 ray tracing cores versus 4 on the 840M, giving it a 24 times advantage in hardware-accelerated ray tracing. The W7900D's pixel rate is 414.0 GPixel/s, which is approximately 17.8 times higher than the 840M's 23.20 GPixel/s. Its texture rate is 827.9 GTexel/s versus 46.40 GTexel/s, a factor of about 17.8 as well. These differences mean the W7900D is suited for high-resolution rendering, multi-display professional setups, and GPU compute tasks.

The AMD Radeon 840M wins in power efficiency and integration. Its 15 W TDP is a fraction of the W7900D's 295 W TDP. The 840M uses system shared memory, which eliminates the need for dedicated VRAM and reduces cost and complexity. It requires no power connectors and occupies an IGP slot width, meaning it fits into ultraportable designs. The 840M's boost clock of 2900 MHz is higher than the W7900D's 2156 MHz boost clock, though the W7900D has far more execution units. The 840M's base clock is 400 MHz versus the W7900D's 1327 MHz base clock. For tasks like basic video playback, office productivity, and light 2D acceleration, the 840M provides sufficient capability while drawing minimal power. The W7900D, with its triple-slot cooler and 2x 8-pin power connectors, requires a desktop workstation chassis with adequate cooling and a power supply rated at 600 W.

Architecture Differences

The two GPUs come from different RDNA generations and target completely different market segments. The AMD Radeon 840M uses the RDNA 3.5 architecture, fabricated on a 4 nm process at TSMC. The AMD Radeon PRO W7900D uses the RDNA 3.0 architecture, fabricated on a 5 nm process at TSMC. The 840M's chip is named Krackan Point and belongs to the Navi III IGP (Strix Point Mobile) generation. The W7900D's chip is named Navi 31, with the codename Plum Bonito, and belongs to the Radeon Pro Navi (Navi III Series) generation.

The W7900D has 57,700 million transistors on a 529 mm² die, yielding a transistor density of 109.1 million transistors per square millimeter. The 840M's transistor count and die size are listed as unknown in the database. The W7900D uses 48 GB of GDDR6 memory on a 384-bit bus, providing 864.0 GB/s of bandwidth. The 840M uses system shared memory with a system dependent bandwidth. Its memory type, bus width, and size are all listed as system shared. This fundamental difference means the W7900D can store and process large datasets entirely on the GPU, while the 840M must compete with the CPU for memory access.

Clock speeds differ significantly. The 840M has a 400 MHz base clock and a 2900 MHz boost clock. The W7900D has a 1327 MHz base clock and a 2156 MHz boost clock, with memory running at 2250 MHz or 18 Gbps effective. The 840M's higher boost clock reflects its smaller, more power-efficient design. Both GPUs support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. Both use PCIe 4.0, but the 840M connects via x8 lanes while the W7900D uses x16 lanes.

The W7900D's display outputs include 3x DisplayPort 2.1 and 1x mini-DisplayPort 2.1. The 840M's display outputs are listed as portable device dependent. The W7900D is 280 mm long, 110 mm high, and 51 mm wide, occupying a triple-slot form factor. The 840M has no listed dimensions because it is an integrated part. The W7900D's predecessor is the Radeon Pro Vega, while the 840M's predecessor is the Navi II IGP. Both products are marked as Active in production status.

FAQ

Q: Which GPU has higher raw compute performance?

A: The AMD Radeon PRO W7900D has an FP32 throughput of 52.99 TFLOPS, which is 34.7 times higher than the AMD Radeon 840M's 1,484.8 GFLOPS. The W7900D also has 6,144 shading units compared to the 840M's 256 shading units.

Q: What memory configurations do these GPUs use?

A: The W7900D has 48 GB of dedicated GDDR6 memory on a 384-bit bus with 864.0 GB/s bandwidth. The 840M uses system shared memory with a system dependent bandwidth and no dedicated VRAM.

Q: Which GPU supports hardware ray tracing?

A: Both GPUs support ray tracing. The W7900D has 96 ray tracing cores, while the 840M has 4 ray tracing cores.

Q: What are the power requirements for each card?

A: The 840M has a TDP of 15 W and requires no power connectors. The W7900D has a TDP of 295 W, requires 2x 8-pin power connectors, and has a suggested PSU rating of 600 W.

Q: Are these GPUs from the same architecture generation?

A: No. The 840M uses RDNA 3.5 architecture on a 4 nm process, while the W7900D uses RDNA 3.0 architecture on a 5 nm process. Both are fabricated by TSMC.

Q: What is the physical size difference between the two?

A: The W7900D is a triple-slot card measuring 280 mm in length, 110 mm in height, and 51 mm in width. The 840M is an IGP with no physical dimensions listed, as it is integrated into a portable device.

Head-to-Head Benchmarks

The database contains no recorded head-to-head benchmark results for these two products. However, the specification data provides a clear quantitative picture. The W7900D's FP32 performance of 52.99 TFLOPS represents a 3,469% advantage over the 840M's 1,484.8 GFLOPS. In pixel throughput, the W7900D's 414.0 GPixel/s outpaces the 840M's 23.20 GPixel/s by a factor of 17.8. Texture rate follows the same pattern: 827.9 GTexel/s versus 46.40 GTexel/s, a 16.8 times difference.

The shading unit count tells a similar story. The W7900D packs 6,144 shading units, which is 24 times the 256 units found on the 840M. The texture mapping unit count is 384 versus 16, a 24 times difference. Render output units are 192 versus 8, also a 24 times difference. Ray tracing cores show a 96 to 4 split, again a 24 times advantage for the W7900D.

Memory bandwidth is where the gap becomes most extreme. The W7900D's 864.0 GB/s of dedicated bandwidth versus the 840M's system dependent shared memory creates an unbridgeable chasm for memory-intensive workloads. The W7900D can feed its 6,144 shading units without contention, while the 840M must share system memory bandwidth with the CPU. The W7900D's 48 GB VRAM capacity allows entire scenes or datasets to reside on the GPU, whereas the 840M has no dedicated VRAM at all.

Clock speeds are the one area where the 840M leads. Its 2900 MHz boost clock exceeds the W7900D's 2156 MHz boost clock by 34.5%. The 840M's base clock of 400 MHz is far lower than the W7900D's 1327 MHz base clock, reflecting the different power envelopes. The 840M's high boost clock is achievable because of its small 15 W power budget, while the W7900D's lower boost clock is offset by its massive parallel execution resources.

The W7900D also leads in memory clock speed. Its memory runs at 2250 MHz with 18 Gbps effective transfer rate. The 840M's memory clock is listed as system shared, meaning it depends entirely on the host system's memory configuration. The W7900D's 384-bit memory bus width is significantly wider than the 840M's system shared bus, which again contributes to the massive bandwidth gap.

Both GPUs support identical API levels: DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. This means software compatibility is not a differentiator. The W7900D's PCIe 4.0 x16 interface provides twice the lane width of the 840M's PCIe 4.0 x8 interface, allowing faster host-to-device transfers for data uploads and downloads. The W7900D's 57,700 million transistors versus the 840M's unknown transistor count further underscores the scale difference. The W7900D's die area of 529 mm² is large enough to accommodate 96 ray tracing cores and 384 TMUs, while the 840M's integrated design on a 4 nm process prioritizes power efficiency over absolute performance. The production status for both is Active, meaning both remain available in the market. The release dates differ, with the 840M released on February 28, 2025, and the W7900D released on September 24, 2025.