AMD Radeon 840M vs Intel Arc B770 Comparison

AMD Radeon 840M and Intel Arc B770 occupy opposite ends of the GPU spectrum, one an integrated processor for thin-and-light laptops, the other a dual-slot add-in board for desktop towers. The recorded data shows a 50th percentile standing for both against all GPUs, but that percentile masks a massive gap in raw specifications and intended workloads. The 840M is built around the Krackan Point chip with RDNA 3.5 architecture, while the B770 uses the BMG-G31 die with Xe2-HPG architecture, placing them in different product generations and performance tiers.

Where Each One Wins

The AMD Radeon 840M is an integrated graphics processor, or IGP, designed for portable devices. Its 15 W thermal design power and lack of power connectors make it suitable for systems where space and cooling are at a premium. The data shows the 840M relies on system shared memory, meaning it draws from the host machine's main RAM rather than dedicated VRAM. This configuration points toward everyday computing, media playback, and light gaming at modest settings. Its classification as an IGP with a portable-device-dependent display output confirms its role in laptops and compact systems.

The Intel Arc B770, by contrast, is a dedicated desktop graphics card with a dual-slot cooler and a 225 W thermal design power. It requires both a 6-pin and an 8-pin power connector and a 550 W suggested power supply. The B770 carries 16 GB of GDDR6 memory on a 256-bit bus, delivering 512.0 GB/s of bandwidth, a figure that dwarfs the system-dependent bandwidth of the 840M. This card targets high-resolution gaming, content creation, and ray-traced workloads. The B770's PCIe 4.0 x16 interface, compared to the 840M's PCIe 4.0 x8, also reflects its position as a bandwidth-hungry desktop part.

The wins split cleanly by form factor and power envelope. The 840M wins in efficiency and portability, as an integrated solution with no additional power draw beyond the host system's existing allocation. The B770 wins in raw throughput, memory capacity, and feature execution, with dedicated silicon and substantially higher clock rates. Neither product attempts to compete in the other's territory, and the data supports that separation clearly.

Architecture Differences

The two GPUs derive from different architectural lineages. The AMD Radeon 840M uses RDNA 3.5, fabricated on a 4 nm process at TSMC, and belongs to the Navi III IGP generation for Strix Point Mobile. The Intel Arc B770 uses Xe2-HPG, built on a 5 nm process also at TSMC, and represents the Battlemage generation within the Arc 7 family. The B770's die measures 368 mm², while the 840M's die size is not recorded in the database.

Compute resources differ dramatically. The 840M contains 256 shading units, 16 texture mapping units, 8 render output units, and 4 ray tracing cores. The B770 scales that up to 4096 shading units, 256 TMUs, 128 ROPs, and 32 ray tracing cores. That is a 16x increase in shading units and an 8x increase in ray tracing cores. The B770 also delivers a pixel rate of 307.2 GPixel/s and a texture rate of 614.4 GTexel/s, compared to 23.20 GPixel/s and 46.40 GTexel/s for the 840M, figures that follow directly from the larger core counts and higher clocks.

Clock behavior differs as well. The 840M has a 400 MHz base clock and a 2900 MHz boost clock, a wide range typical of integrated parts that scale with thermal headroom. The B770 operates at a 2100 MHz base and 2400 MHz boost, a much narrower range that reflects a sustained desktop workload profile. Memory architecture is fundamentally different: the 840M uses system shared memory with system-dependent bandwidth, while the B770 uses dedicated GDDR6 at 2000 MHz with 16 Gbps effective speed across a 256-bit bus.

Both GPUs support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4, so API feature parity exists at the software level. The B770 adds specific display outputs, including 1x HDMI 2.1a and 3x DisplayPort 2.1, while the 840M's outputs depend on the portable device it is integrated into. The B770's predecessor is Alchemist, while the 840M's predecessor is Navi II IGP.

Head-to-Head Benchmarks

The head-to-head benchmark set contains no entries, so direct performance comparisons must be derived from the specification data. The largest numerical advantage for the Intel Arc B770 appears in floating-point throughput. The B770 delivers 19.66 TFLOPS of FP32 performance, while the 840M delivers 1,484.8 GFLOPS, which converts to approximately 1.48 TFLOPS. The B770 leads by a factor of roughly 13.2x in FP32 compute. In FP16, the B770 reaches 39.32 TFLOPS with a 2:1 ratio, while the 840M stays at 1,484.8 GFLOPS with a 1:1 ratio, so the B770's FP16 advantage is even larger at approximately 26.5x.

Memory bandwidth shows a similarly one-sided comparison. The B770's 512.0 GB/s bandwidth is a fixed hardware figure, while the 840M's bandwidth is listed as system dependent, meaning it varies with the host platform's memory configuration. That dependency prevents a direct numeric comparison, but the B770's dedicated GDDR6 implementation with a 256-bit bus provides a structural advantage that system shared memory cannot match for sustained throughput.

The B770 also leads in pixel and texture throughput by wide margins. Its pixel rate of 307.2 GPixel/s is 13.2x higher than the 840M's 23.20 GPixel/s. Its texture rate of 614.4 GTexel/s is 13.2x higher than the 840M's 46.40 GTexel/s. These multiples align with the shading unit and TMU ratios, confirming that the B770's advantage scales consistently across the rendering pipeline.

The AMD Radeon 840M holds advantages in power efficiency and clock flexibility. Its 15 W TDP is 15x lower than the B770's 225 W. Its boost clock of 2900 MHz exceeds the B770's 2400 MHz boost by 500 MHz, and its base clock of 400 MHz is dramatically lower than the B770's 2100 MHz, reflecting a design that idles low and ramps high when needed. The 840M also requires no external power connectors, while the B770 needs a 6-pin and an 8-pin connector.

FAQ

Q: Which GPU has more shading units?

A: The Intel Arc B770 has 4096 shading units, while the AMD Radeon 840M has 256. The B770's count is 16x higher.

Q: How does memory capacity compare between the two?

A: The Intel Arc B770 has 16 GB of dedicated GDDR6 memory on a 256-bit bus. The AMD Radeon 840M uses system shared memory, with size, type, and bus width all listed as system shared.

Q: What are the power requirements for each GPU?

A: The AMD Radeon 840M has a 15 W TDP and requires no power connectors. The Intel Arc B770 has a 225 W TDP, requires a 6-pin and an 8-pin power connector, and suggests a 550 W power supply.

Q: Do both GPUs support the same graphics APIs?

A: Yes. Both support DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Q: Which GPU has the higher boost clock?

A: The AMD Radeon 840M has a boost clock of 2900 MHz, which is 500 MHz higher than the Intel Arc B770's 2400 MHz boost clock.

Q: What is the memory bandwidth of the Intel Arc B770?

A: The Intel Arc B770 has 512.0 GB/s of memory bandwidth. The AMD Radeon 840M's bandwidth is system dependent.

Specification Differences

The two GPUs differ across nearly every measurable specification. Process node: 4 nm for the 840M versus 5 nm for the B770. Die size: unknown for the 840M versus 368 mm² for the B770. Base clock: 400 MHz versus 2100 MHz. Boost clock: 2900 MHz versus 2400 MHz. Memory size: system shared versus 16 GB. Memory type: system shared versus GDDR6. Bus width: system shared versus 256 bit. Bandwidth: system dependent versus 512.0 GB/s.

Shading units: 256 versus 4096. Texture mapping units: 16 versus 256. Render output units: 8 versus 128. Ray tracing cores: 4 versus 32. Pixel rate: 23.20 GPixel/s versus 307.2 GPixel/s. Texture rate: 46.40 GTexel/s versus 614.4 GTexel/s. FP32 performance: 1,484.8 GFLOPS versus 19.66 TFLOPS. FP16 performance: 1,484.8 GFLOPS (1:1) versus 39.32 TFLOPS (2:1).

TDP: 15 W versus 225 W. Slot width: IGP versus dual-slot. Power connectors: none versus 1x 6-pin and 1x 8-pin. Suggested PSU: not listed versus 550 W. Bus interface: PCIe 4.0 x8 versus PCIe 4.0 x16. Display outputs: portable device dependent versus 1x HDMI 2.1a and 3x DisplayPort 2.1. Release date: 2025-02-28 versus 2025-12-31. Predecessor: Navi II IGP versus Alchemist. Production status: active versus not listed.

The Verdict

The recorded data points to two different purchasing decisions depending on the target system. For a portable device where the GPU must share power and thermal budget with the CPU, the AMD Radeon 840M is the only viable choice among these two. Its 15 W TDP, integrated form factor, and lack of power connectors make it suitable for laptops and compact systems. Its 2900 MHz boost clock and RDNA 3.5 architecture provide reasonable graphics capability within that constraint, and its system shared memory model eliminates the need for dedicated VRAM allocation.

For a desktop system with a 550 W power supply and room for a dual-slot card, the Intel Arc B770 delivers the performance the 840M cannot approach. The B770's 4096 shading units, 16 GB of GDDR6, and 512.0 GB/s bandwidth place it in a different performance class entirely. Its 19.66 TFLOPS FP32 throughput and 32 ray tracing cores support demanding gaming and compute workloads, and its dedicated display outputs enable multi-monitor setups directly.

Choosing between them requires no trade-off analysis because the products do not overlap. The 840M is an integrated solution for portable devices, and the B770 is a dedicated desktop card. The data shows no head-to-head benchmark results because no reasonable test scenario would place them in direct competition. The 840M wins on efficiency and portability, while the B770 wins on every measure of raw performance, from compute throughput to memory bandwidth to pixel output.