AMD Radeon 840M vs AMD Steam Deck OLED GPU Comparison

FAQ

Q: Which GPU has the higher boost clock?

A: The AMD Radeon 840M boosts to 2900 MHz, while the AMD Steam Deck OLED GPU boosts to 1600 MHz. The Radeon 840M has a base clock of 400 MHz, whereas the Steam Deck OLED GPU has a base clock of 1000 MHz.

Q: How do the shading unit counts compare between the two GPUs?

A: The AMD Steam Deck OLED GPU has 512 shading units, exactly double the 256 shading units found in the AMD Radeon 840M. The Steam Deck OLED GPU also has 32 texture mapping units and 16 ROPs, compared to 16 TMUs and 8 ROPs on the Radeon 840M.

Q: What is the process node difference between these chips?

A: The AMD Radeon 840M uses a 4 nm process from TSMC, while the AMD Steam Deck OLED GPU uses a 6 nm process from TSMC. The Steam Deck OLED GPU is built from 2,400 million transistors on a 131 mm² die, whereas the Radeon 840M's transistor count and die size are listed as unknown.

Q: Which GPU has dedicated memory, and what is its bandwidth?

A: The AMD Steam Deck OLED GPU has 16 GB of LPDDR5 memory on a 128-bit bus, delivering 176.0 GB/s of bandwidth. The AMD Radeon 840M uses System Shared memory with bandwidth described as System Dependent.

Q: What are the ray tracing core counts for each GPU?

A: The AMD Steam Deck OLED GPU has 8 ray tracing cores, while the AMD Radeon 840M has 4 ray tracing cores. Both support DirectX 12 Ultimate (12_2) and OpenGL 4.6, though the Radeon 840M supports Vulkan 1.4 and the Steam Deck OLED GPU supports Vulkan 1.3.

Q: What are the physical dimensions of the Steam Deck OLED GPU?

A: The AMD Steam Deck OLED GPU measures 298 mm in length (11.7 inches), 117 mm in height (4.6 inches), and 49 mm in width (1.9 inches). The Radeon 840M is an IGP with no listed dimensions or slot width.

Architecture Differences

The AMD Radeon 840M and AMD Steam Deck OLED GPU represent two distinct architectural generations from the same manufacturer. The Radeon 840M is built on RDNA 3.5 and belongs to the Navi III IGP (Strix Point Mobile) generation, while the Steam Deck OLED GPU uses RDNA 2.0 and is classified as a Console GPU from Valve. This architectural gap is the primary driver behind their different feature sets and performance characteristics.

The manufacturing process differs significantly. The Radeon 840M uses a 4 nm TSMC node, while the Steam Deck OLED GPU uses a 6 nm TSMC node. The Steam Deck OLED GPU has a known transistor count of 2,400 million on a 131 mm² die, resulting in a transistor density of 18.3 million per mm². The Radeon 840M's transistor count and die size are recorded as unknown, though its smaller process node suggests a denser implementation.

Compute resource allocation is sharply divergent. The Steam Deck OLED GPU carries 512 shading units, 32 TMUs, and 16 ROPs, all double the Radeon 840M's 256 shading units, 16 TMUs, and 8 ROPs. Ray tracing hardware follows the same pattern: the Steam Deck OLED GPU has 8 RT cores, the Radeon 840M has 4. Despite having fewer execution units, the Radeon 840M reaches a much higher boost clock of 2900 MHz versus 1600 MHz on the Steam Deck OLED GPU.

Memory architecture is a fundamental differentiator. The Radeon 840M relies on system shared memory with a bus width and type both described as System Shared, and bandwidth is System Dependent. The Steam Deck OLED GPU has dedicated 16 GB LPDDR5 memory on a 128-bit bus with a fixed 176.0 GB/s bandwidth, plus a memory clock of 1375 MHz with 11 Gbps effective speed. This gives the Steam Deck OLED GPU predictable memory performance, while the Radeon 840M's memory throughput depends entirely on the host system.

API support shows minor differences. Both GPUs support DirectX 12 Ultimate (12_2) and OpenGL 4.6. The Radeon 840M supports Vulkan 1.4, while the Steam Deck OLED GPU supports Vulkan 1.3. The Radeon 840M uses a PCIe 4.0 x8 bus interface, whereas the Steam Deck OLED GPU has no listed bus interface. Display outputs also differ: the Radeon 840M is Portable Device Dependent, while the Steam Deck OLED GPU has a single USB Type-C output.

The Verdict

The recorded data points to a clear split based on workload type. The AMD Radeon 840M delivers substantially higher raw compute throughput per clock thanks to its 2900 MHz boost, but it does not carry any benchmark scores in the database. The AMD Steam Deck OLED GPU also has no recorded benchmark scores, so direct performance comparisons must rely on architectural specifications.

For scenarios requiring maximum floating-point throughput from a compact integrated solution, the Radeon 840M's FP32 performance of 1,484.8 GFLOPS matches its FP16 throughput at a 1:1 ratio, indicating no FP16 acceleration advantage. The Steam Deck OLED GPU delivers 1.638 TFLOPS FP32 and 3.277 TFLOPS FP16 at a 2:1 ratio, meaning it can double its throughput when using FP16 workloads. This makes the Steam Deck OLED GPU the stronger choice for workloads that can exploit FP16 arithmetic.

The Steam Deck OLED GPU's dedicated 16 GB memory pool with 176.0 GB/s bandwidth removes dependency on system memory performance, which is critical for consistent frame delivery in gaming. The Radeon 840M's System Shared memory makes its performance contingent on the host laptop or handheld's memory configuration, a variable that can swing results significantly.

For ray tracing workloads, the Steam Deck OLED GPU has twice the RT core count (8 versus 4), giving it a structural advantage in that feature set. The Radeon 840M counters with a newer architecture, RDNA 3.5 versus RDNA 2.0, which may include efficiency improvements that partially offset the older design's raw resource deficit.

Users who prioritize a single integrated GPU with predictable memory characteristics and higher compute unit counts should select the Steam Deck OLED GPU. Users who need a modern IGP with a newer architecture, higher boost clocks, and PCIe 4.0 x8 connectivity should select the Radeon 840M. Both are rated at 15 W TDP, so power consumption is not a differentiator in this comparison.

Specification Differences

The two GPUs differ across nearly every major specification category. The process node is 4 nm for the Radeon 840M versus 6 nm for the Steam Deck OLED GPU. The Radeon 840M's chip is Krackan Point, while the Steam Deck OLED GPU uses Sephiroth. The Radeon 840M belongs to the Navi III IGP (Strix Point Mobile) generation, and the Steam Deck OLED GPU is classified as a Console GPU from Valve.

Clock speeds differ dramatically: the Radeon 840M has a base of 400 MHz and boost of 2900 MHz; the Steam Deck OLED GPU has a base of 1000 MHz and boost of 1600 MHz. The Steam Deck OLED GPU has a defined memory clock of 1375 MHz with 11 Gbps effective speed; the Radeon 840M's memory clock is System Shared.

Memory configuration is entirely different. The Radeon 840M has System Shared memory size, type, bus width, and System Dependent bandwidth. The Steam Deck OLED GPU has 16 GB of LPDDR5 memory on a 128-bit bus with 176.0 GB/s bandwidth.

Compute unit counts are doubled on the Steam Deck OLED GPU: 512 shading units versus 256, 32 TMUs versus 16, 16 ROPs versus 8, and 8 RT cores versus 4. Pixel rate is 25.60 GPixel/s on the Steam Deck OLED GPU versus 23.20 GPixel/s on the Radeon 840M. Texture rate is 51.20 GTexel/s versus 46.40 GTexel/s.

FP32 throughput is 1.638 TFLOPS on the Steam Deck OLED GPU, which is higher than the Radeon 840M's 1,484.8 GFLOPS. FP16 throughput is 3.277 TFLOPS (2:1) on the Steam Deck OLED GPU versus 1,484.8 GFLOPS (1:1) on the Radeon 840M.

The Radeon 840M has a PCIe 4.0 x8 bus interface; the Steam Deck OLED GPU has none listed. Display outputs are Portable Device Dependent on the Radeon 840M versus 1x USB Type-C on the Steam Deck OLED GPU. Vulkan support is 1.4 versus 1.3. The Steam Deck OLED GPU has physical dimensions of 298 mm by 117 mm by 49 mm; the Radeon 840M is an IGP with no dimensions. The Radeon 840M has no power connectors and is an IGP slot width; the Steam Deck OLED GPU has no listed slot width or power connectors. The Radeon 840M was released on 2025-02-28, and the Steam Deck OLED GPU on 2023-11-08. The Radeon 840M's predecessor is Navi II IGP; the Steam Deck OLED GPU has no predecessor listed. The Steam Deck OLED GPU has a transistor count of 2,400 million on a 131 mm² die; the Radeon 840M's transistor and die data are unknown.

Head-to-Head Benchmarks

The database contains no recorded benchmark scores for either GPU, and the head-to-head benchmark list is empty. Both GPUs have an average benchmark score of 0 and a percentile rank of 50 against all GPUs. There are no nearest rivals listed for either product, and the wins counter shows 0 for both sides.

Without direct benchmark measurements, the comparison must rely on the specification data recorded in the database. The Steam Deck OLED GPU wins on raw compute resources: it has 512 shading units, 32 TMUs, 16 ROPs, and 8 RT cores, each exactly double the corresponding counts on the Radeon 840M. This doubling translates to higher theoretical pixel rate (25.60 GPixel/s versus 23.20 GPixel/s) and texture rate (51.20 GTexel/s versus 46.40 GTexel/s).

The Radeon 840M wins on clock speed: its 2900 MHz boost is 81% higher than the Steam Deck OLED GPU's 1600 MHz boost. This clock advantage partially compensates for the lower unit counts, though the FP32 output of 1,484.8 GFLOPS still trails the Steam Deck OLED GPU's 1.638 TFLOPS. The Radeon 840M's FP16 output equals its FP32 at 1,484.8 GFLOPS, while the Steam Deck OLED GPU's FP16 output of 3.277 TFLOPS is double its FP32, giving it a 2.2x advantage in FP16 throughput.

Memory bandwidth is a decisive win for the Steam Deck OLED GPU with 176.0 GB/s of fixed LPDDR5 bandwidth versus System Dependent bandwidth on the Radeon 840M. The Steam Deck OLED GPU also benefits from a defined 16 GB memory capacity, whereas the Radeon 840M's memory size is System Shared and thus variable.

Architecture generation favors the Radeon 840M with RDNA 3.5 versus RDNA 2.0, and it also supports the newer Vulkan 1.4 API. The Radeon 840M's PCIe 4.0 x8 interface provides a modern bus connection, while the Steam Deck OLED GPU has no listed bus interface.

Where Each One Wins

The AMD Steam Deck OLED GPU wins in scenarios that demand high compute unit counts and predictable memory performance. Its 512 shading units and 8 RT cores make it structurally superior for parallel workloads such as rasterization-heavy gaming and ray tracing effects. The dedicated 16 GB LPDDR5 pool with 176.0 GB/s bandwidth ensures consistent memory throughput regardless of host system configuration, which is essential for handheld gaming where system memory is shared with the CPU.

The AMD Radeon 840M wins in scenarios that benefit from a newer architecture and higher clock speeds. Its RDNA 3.5 architecture is two generations newer than RDNA 2.0, potentially offering better instructions per clock. The 2900 MHz boost clock is nearly double the Steam Deck OLED GPU's 1600 MHz boost, which can improve latency-sensitive workloads. The PCIe 4.0 x8 interface allows for faster communication with the host system compared to the Steam Deck OLED GPU's unlisted bus interface.

For FP16-heavy workloads, the Steam Deck OLED GPU is the clear winner with 3.277 TFLOPS versus 1,484.8 GFLOPS on the Radeon 840M. The 2:1 FP16 ratio on the Steam Deck OLED GPU means it can process half-precision arithmetic at twice its FP32 rate, a feature absent on the Radeon 840M, which runs FP16 at a 1:1 ratio.

For FP32 workloads, the Steam Deck OLED GPU also holds the advantage: 1.638 TFLOPS versus 1,484.8 GFLOPS, a margin of roughly 10%. This makes the Steam Deck OLED GPU the better choice for general-purpose compute and game rendering that relies on FP32 shaders.

The Radeon 840M wins on integration flexibility. As an IGP with no power connectors and a 15 W TDP, it is designed for portable devices where space and power are constrained. The Steam Deck OLED GPU is a console-class part with physical dimensions of 298 mm by 117 mm by 49 mm, making it suitable for a dedicated handheld form factor.

Vulkan users should prefer the Radeon 840M for its 1.4 API support, while the Steam Deck OLED GPU's 1.3 support remains functional but older. DirectX and OpenGL support are identical at 12 Ultimate (12_2) and 4.6 respectively, so those APIs do not differentiate the two.

Both GPUs share a 15 W TDP, meaning thermal and power design targets are equivalent. The decision between them should be driven by workload type: the Steam Deck OLED GPU for compute-heavy and memory-sensitive tasks, the Radeon 840M for modern architecture features and clock speed advantages.