AMD Radeon R7 M340 vs NVIDIA GeForce 840M Comparison

The NVIDIA GeForce 840M and AMD Radeon R7 M340 are two end-of-life mobile graphics solutions that occupy nearly the same performance tier, yet they achieve their results through markedly different design philosophies. The data shows a split decision: the 840M wins the Geekbench OpenCL test with a score of 5764 against 4932, while the R7 M340 counters in Geekbench Vulkan with 5193 versus 4880. Their average benchmark scores are close—5322 for NVIDIA and 5063 for AMD—placing them at the 31st and 30th percentiles of all GPUs, respectively. This proximity in overall standing makes the specific architectural and API-level differences the deciding factors for any given workload.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The NVIDIA GeForce 840M leads with an average benchmark score of 5322, compared to the AMD Radeon R7 M340’s 5063. This places the 840M at the 31st percentile of all GPUs, while the R7 M340 sits just one percentile behind at 30.

Q: How do the two GPUs compare in the Geekbench OpenCL test?

A: The NVIDIA GeForce 840M is the clear winner in OpenCL, scoring 5764 against the R7 M340’s 4932. That is a 16.9% advantage in favor of the NVIDIA part, representing the largest performance gap between the two in any benchmark.

Q: Does the AMD Radeon R7 M340 win any benchmark?

A: Yes, the R7 M340 takes the Geekbench Vulkan test with a score of 5193, while the 840M trails at 4880. The deltaPct here is -6, meaning the NVIDIA GPU is 6% behind AMD’s offering in this specific API workload.

Q: What is the transistor and die size difference between the two chips?

A: The AMD Radeon R7 M340’s Meso chip contains 1,550 million transistors on a 125 mm² die, while the NVIDIA GeForce 840M’s GM108S packs 1,020 million transistors onto a much smaller 77 mm² die. This results in a higher transistor density for the NVIDIA chip at 13.2M per mm², versus 12.4M per mm² for the AMD part.

Q: How do their shading unit counts and texture rates compare?

A: The NVIDIA GeForce 840M has more shading units at 384, compared to 320 for the AMD Radeon R7 M340. However, the AMD chip has more texture mapping units (20 vs 16), giving it a higher texture rate of 20.42 GTexel/s, while NVIDIA’s texture rate is 17.98 GTexel/s.

Q: What API versions do each GPU support at their maximum?

A: The AMD Radeon R7 M340 supports DirectX 12 (12_0) and Vulkan 1.2.170, whereas the NVIDIA GeForce 840M is limited to DirectX 12 (11_0) but offers a newer Vulkan 1.4 implementation. Both support OpenGL 4.6.

The Verdict

The benchmark results indicate that neither GPU is a universal winner, so the choice hinges on the application’s API preference. The NVIDIA GeForce 840M is the pick for compute-heavy OpenCL workloads, where its 16.9% lead over the R7 M340 is substantial. Its higher average benchmark score (5322 vs 5063) and superior transistor density (13.2M/mm² vs 12.4M/mm²) suggest a more efficient design for raw number crunching.

Conversely, the AMD Radeon R7 M340 is the better option for Vulkan-based rendering tasks. Its 6% advantage in that benchmark, combined with a higher texture rate (20.42 GTexel/s) and full DirectX 12 (12_0) feature support, indicates a stronger fit for modern graphics APIs that leverage those capabilities. The R7 M340 also offers more total transistors (1,550 million vs 1,020 million), which could be relevant for workloads that scale with raw compute resources.

For users who prioritize OpenCL compute or prefer the NVIDIA ecosystem’s newer Vulkan 1.4 support, the 840M is the logical choice. For those targeting DirectX 12 (12_0) titles or Vulkan-specific rendering pipelines, the R7 M340 holds a measurable edge. The data ultimately shows a 1-1 win split, so the deciding factor is which benchmark test aligns with the user’s primary software.

Head-to-Head Benchmarks

The most decisive result comes from the Geekbench OpenCL test, where the NVIDIA GeForce 840M scores 5764 against the AMD Radeon R7 M340’s 4932. This 832-point gap translates to a 16.9% performance advantage for NVIDIA, a margin that clearly separates the two in general-purpose compute tasks. The 840M’s higher shading unit count (384 vs 320) and boost clock of 1124 MHz, compared to 1021 MHz on the AMD part, likely contribute to this outcome.

The tables turn in the Geekbench Vulkan test, where the AMD Radeon R7 M340 posts a score of 5193, surpassing the NVIDIA GeForce 840M’s 4880. The deltaPct of -6% indicates that the 840M is 6% slower in this API. This result suggests that AMD’s GCN 3.0 architecture handles Vulkan’s low-level overhead more effectively, despite having a lower base clock (943 MHz vs 1029 MHz) and fewer shading units.

Looking at the nearest rivals for context, the 840M’s average score of 5322 places it just 0.1% ahead of the NVIDIA GeForce 930A (5317) and 0.3% ahead of the GTX 980M (5308), though it trails the AMD Radeon R7 M445 by 0.7%. The R7 M340’s average of 5063 is exactly tied with the AMD Radeon R7 240, while it leads the FirePro W4170M by 0.6% and the Radeon R5 M430 by 0.9%. This shows that both chips are tightly clustered with their immediate competitors, making the head-to-head delta of 16.9% in OpenCL and 6% in Vulkan particularly significant within their respective performance strata.

Specification Differences

The two GPUs diverge primarily in their core configurations and clock speeds. The NVIDIA GeForce 840M operates at a base clock of 1029 MHz with a boost up to 1124 MHz, while the AMD Radeon R7 M340 runs at 943 MHz base and 1021 MHz boost—a difference of 86 MHz at base and 103 MHz at boost. This clock advantage helps the 840M achieve a higher pixel rate of 8.992 GPixel/s, versus 8.168 GPixel/s for the AMD part.

Shader and texture resources also differ. The 840M has 384 shading units and 16 TMUs, while the R7 M340 has 320 shading units and 20 TMUs. This results in the NVIDIA chip leading in FP32 performance at 863.2 GFLOPS, compared to 653.4 GFLOPS for the AMD chip. However, the R7 M340’s extra TMUs give it a higher texture rate of 20.42 GTexel/s, against 17.98 GTexel/s for the 840M. Both share 8 ROPs and a 64-bit memory bus.

Memory configurations are nearly identical: both use 2 GB of DDR3 with a 64-bit bus width and effective speeds of 2 Gbps. The NVIDIA part edges out a slightly higher bandwidth at 16.02 GB/s, while the AMD part is at 16.00 GB/s. The 840M is specified with a 33 W TDP and an IGP slot width, while the R7 M340’s TDP and slot width are not listed. Both connect via PCIe 3.0 x8.

Architecture Differences

The underlying architectures are fundamentally different. The NVIDIA GeForce 840M is built on the Maxwell architecture using the GM108S chip, while the AMD Radeon R7 M340 employs GCN 3.0 with the Meso chip. Both are fabricated on a 28 nm process at TSMC, but the design philosophies diverge sharply.

The AMD chip is physically larger, with a die size of 125 mm² and 1,550 million transistors, whereas the NVIDIA chip measures just 77 mm² with 1,020 million transistors. This means the R7 M340 has roughly 52% more transistor count and a 62% larger die area. Interestingly, the NVIDIA chip achieves a higher transistor density at 13.2M per mm², compared to 12.4M per mm² for AMD, indicating a more compact layout for the Maxwell design.

Feature support also separates them. The AMD Radeon R7 M340 supports DirectX 12 (12_0) and Vulkan 1.2.170, while the NVIDIA GeForce 840M is capped at DirectX 12 (11_0) but supports the newer Vulkan 1.4. The AMD part also lists FP16 performance at 653.4 GFLOPS (1:1), while the NVIDIA part has no FP16 data. The R7 M340 belongs to the Gem System (R7 M300) generation, succeeding the Solar System line, whereas the 840M is part of the GeForce 800M generation, following the GeForce 700M and preceding the GeForce 900M. Their release dates differ, with the 840M launching earlier and the R7 M340 arriving later.

Where Each One Wins

The NVIDIA GeForce 840M is the definitive winner in OpenCL compute performance, with a 16.9% lead that makes it the stronger choice for applications relying on this API. Its higher average benchmark score (5322 vs 5063) and superior FP32 throughput (863.2 GFLOPS) reinforce this position. The 840M also holds advantages in pixel rate (8.992 GPixel/s) and memory bandwidth (16.02 GB/s), which could benefit tasks that are sensitive to these specific throughput metrics. Its newer Vulkan 1.4 support means it is better positioned for software that leverages this latest API revision, even if its actual Vulkan score is lower.

The AMD Radeon R7 M340 wins the Vulkan benchmark decisively, with a 6% advantage that suggests its GCN 3.0 architecture is more efficient at handling this API’s command buffer and draw call overhead. Its higher texture rate (20.42 GTexel/s) and extra TMUs (20 vs 16) make it the better fit for texture-heavy rendering workloads. The R7 M340’s full DirectX 12 (12_0) feature set is a meaningful advantage for modern Windows games that require this level of API support, whereas the 840M is limited to 11_0 features. For users running Vulkan-based titles or DirectX 12 (12_0) applications, the R7 M340’s benchmark and feature profile make it the more capable option, despite losing the average score contest.