AMD Radeon R5 M420 vs NVIDIA GeForce 825M Comparison

The AMD Radeon R5 M420 and NVIDIA GeForce 825M are both end-of-life mobile graphics processors aimed at entry-level laptops, and the benchmark data provides a clear, if narrow, picture of their relative performance. In the sole standardized test available, the Geekbench OpenCL benchmark, the AMD part scores 3956 against the NVIDIA part's 3694, yielding a 7.1% victory for the Radeon R5 M420. This single data point places the AMD GPU at the 23rd percentile of all GPUs, while the NVIDIA GPU sits at the 22nd percentile, confirming that both are firmly in the entry-level tier, but with a measurable performance gap between them.

Head-to-Head Benchmarks

The only head-to-head benchmark result in the data is Geekbench OpenCL, and the AMD Radeon R5 M420 wins decisively. The scores are 3956 for the AMD part and 3694 for the NVIDIA GeForce 825M, translating to a 7.1% delta in favor of AMD. This is not a marginal difference; it represents a clear, consistent advantage in this compute-oriented workload, which often correlates with general GPU throughput.

To contextualize the AMD Radeon R5 M420's score, its nearest rivals in the database are the NVIDIA GeForce 830M (average score 3957, deltaPct 0), the NVIDIA GeForce GT 745M (average score 3953, deltaPct 0.1), and the NVIDIA Quadro K2000 (average score 3964, deltaPct -0.2). The R5 M420's score of 3956 places it in a virtual tie with these three competitors, all within a 0.2% margin. This suggests the AMD chip is performing at the expected level for its class, matching comparable NVIDIA solutions from a similar era.

The NVIDIA GeForce 825M's score of 3694, meanwhile, is most closely matched by the NVIDIA GeForce GT 740M (average score 3717, deltaPct -0.6) and the NVIDIA Quadro 3000M (average score 3718, deltaPct -0.6). It also sits slightly above the AMD Radeon HD 6770 (average score 3649, deltaPct 1.2). The fact that the GeForce 825M is 0.6% behind the GT 740M indicates it is one of the slower members of its own family. The 7.1% delta between the two reviewed GPUs is therefore significant, as it places the AMD part in a higher performance bracket entirely, rubbing shoulders with the GeForce 830M rather than the lower-tier GeForce 825M.

Architecture Differences

The two GPUs come from different architectural generations and design philosophies. The AMD Radeon R5 M420 is built on the GCN 1.0 architecture, using the "Jet" chip, while the NVIDIA GeForce 825M utilizes the Kepler 2.0 architecture with the "GK208" chip. Both are manufactured on a 28 nm process at TSMC, but the underlying designs diverge significantly.

The most striking difference is in physical size and complexity. The AMD chip contains 690 million transistors on a die size of 56 mm², resulting in a transistor density of 12.3M / mm². The NVIDIA chip is substantially larger, packing 1,020 million transistors onto an 87 mm² die, though its transistor density is slightly lower at 11.7M / mm². This means the NVIDIA GPU has roughly 48% more transistors, but they are spread across a larger area, suggesting a different design focus.

Core configurations also differ. The AMD Radeon R5 M420 features 320 shading units, 20 texture mapping units (TMUs), and 8 raster operation units (ROPs). The NVIDIA GeForce 825M, in contrast, offers 384 shading units, 32 TMUs, and 8 ROPs. The NVIDIA part has more shading units and significantly more TMUs, which typically translates to higher texture fill rates. Indeed, the texture rate for the NVIDIA part is 30.11 GTexel/s, compared to 17.00 GTexel/s for the AMD part. The pixel rates are closer, with the NVIDIA part at 7.528 GPixel/s and the AMD part at 6.800 GPixel/s.

Clock speeds favor NVIDIA in both base and boost states. The GeForce 825M runs at a base clock of 850 MHz with a boost up to 941 MHz, while the Radeon R5 M420 operates at 780 MHz base and 850 MHz boost. However, the AMD part has a significant advantage in memory clock speed, with its DDR3 memory running at 1000 MHz (2 Gbps effective) compared to the NVIDIA's 900 MHz (1800 Mbps effective). This partially offsets the NVIDIA core advantages.

Memory configuration is another major differentiator. The AMD Radeon R5 M420 comes with 4 GB of DDR3 memory on a 64-bit bus, delivering 16.00 GB/s of bandwidth. The NVIDIA GeForce 825M has only 1024 MB of DDR3 memory on the same 64-bit bus, yielding 14.40 GB/s of bandwidth. The AMD part offers four times the memory capacity and roughly 11% more bandwidth, which can be critical for modern workloads that exceed 1 GB of frame buffer usage.

The two also differ in API support. The AMD part supports DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.170. The NVIDIA part supports DirectX 12 (11_0), OpenGL 4.6, and Vulkan 1.2.175. While both support DirectX 12, the feature levels differ slightly, and the AMD part has a marginally higher DirectX feature level, while the NVIDIA part has a slightly newer Vulkan version.

Where Each One Wins

The benchmark data shows the AMD Radeon R5 M420 winning the only direct comparison, but the architectural breakdown reveals a more nuanced picture for different use cases.

For compute-heavy tasks, the AMD Radeon R5 M420 is the clear winner. Its 7.1% lead in Geekbench OpenCL is the most direct evidence. This advantage is likely bolstered by its higher memory bandwidth (16.00 GB/s vs 14.40 GB/s) and its larger 4 GB frame buffer, which prevents memory swapping in data-intensive workloads. The AMD part's 544.0 GFLOPS of FP32 performance, while lower than the NVIDIA's 722.7 GFLOPS, still manages to win the compute benchmark, suggesting that the GCN architecture is more efficient in this specific test or that the memory subsystem provides a critical advantage.

For texture-heavy graphics workloads, the NVIDIA GeForce 825M appears to have the theoretical edge. Its 32 TMUs and 30.11 GTexel/s texture rate are far superior to the AMD's 20 TMUs and 17.00 GTexel/s. This suggests the NVIDIA part would excel in games or applications that rely heavily on texture mapping. Similarly, its higher FP32 throughput of 722.7 GFLOPS and higher boost clock of 941 MHz indicate a stronger raw compute peak, even if the OpenCL benchmark tells a different story.

For gaming with large textures or modern game assets, the AMD part's 4 GB memory capacity is a significant practical advantage. The NVIDIA part's 1024 MB frame buffer is likely to be a bottleneck in any scenario requiring more than 1 GB of video memory, which includes many recent titles at moderate settings. The AMD part's higher bandwidth also helps maintain smoother performance in memory-constrained situations.

For power-sensitive applications, the data shows the NVIDIA GeForce 825M has a specified TDP of 33 W, while the AMD Radeon R5 M420's TDP is not listed. This makes direct power comparison impossible, but the presence of a TDP figure for the NVIDIA part suggests it has a known, manageable power envelope for mobile use.

FAQ

Q: Which GPU is faster in the available benchmark data?

A: The AMD Radeon R5 M420 scores 3956 in Geekbench OpenCL, which is 7.1% higher than the NVIDIA GeForce 825M's score of 3694.

Q: How does the AMD Radeon R5 M420 compare to its nearest rivals?

A: The AMD part's score of 3956 is effectively tied with the NVIDIA GeForce 830M (3957, 0% delta) and the NVIDIA GeForce GT 745M (3953, 0.1% delta), placing it in a competitive position against those GPUs.

Q: What is the memory capacity difference between the two GPUs?

A: The AMD Radeon R5 M420 has 4 GB of DDR3 memory, while the NVIDIA GeForce 825M has 1024 MB (1 GB) of DDR3 memory, a fourfold difference in capacity.

Q: Does the NVIDIA GPU have any specification advantages?

A: Yes, the NVIDIA GeForce 825M has more shading units (384 vs 320), more TMUs (32 vs 20), a higher boost clock (941 MHz vs 850 MHz), and a higher texture rate (30.11 GTexel/s vs 17.00 GTexel/s).

Q: What is the transistor count for each chip?

A: The AMD Radeon R5 M420's Jet chip contains 690 million transistors, while the NVIDIA GeForce 825M's GK208 chip contains 1,020 million transistors.

Q: Which GPU has a higher memory bandwidth?

A: The AMD Radeon R5 M420 has a bandwidth of 16.00 GB/s, which is higher than the NVIDIA GeForce 825M's 14.40 GB/s.

Specification Differences

| Specification | AMD Radeon R5 M420 | NVIDIA GeForce 825M |

|----------------|---------------------|----------------------|

| Architecture | GCN 1.0 | Kepler 2.0 |

| Chip | Jet | GK208 |

| Transistors | 690 million | 1,020 million |

| Die Size | 56 mm² | 87 mm² |

| Transistor Density | 12.3M / mm² | 11.7M / mm² |

| Base Clock | 780 MHz | 850 MHz |

| Boost Clock | 850 MHz | 941 MHz |

| Memory Clock | 1000 MHz (2 Gbps) | 900 MHz (1800 Mbps) |

| Memory Size | 4 GB | 1024 MB |

| Memory Bandwidth | 16.00 GB/s | 14.40 GB/s |

| Shading Units | 320 | 384 |

| TMUs | 20 | 32 |

| Pixel Rate | 6.800 GPixel/s | 7.528 GPixel/s |

| Texture Rate | 17.00 GTexel/s | 30.11 GTexel/s |

| FP32 | 544.0 GFLOPS | 722.7 GFLOPS |

| TDP | Not listed | 33 W |

| DirectX | 12 (11_1) | 12 (11_0) |

| Vulkan | 1.2.170 | 1.2.175 |

| Release Date | 2016-05-14 | 2014-01-26 |

The Verdict

Based strictly on the benchmark data, the AMD Radeon R5 M420 is the better-performing GPU. Its 7.1% lead in Geekbench OpenCL is a decisive margin that places it in a higher performance tier, matching the NVIDIA GeForce 830M rather than the slower GeForce 825M. The AMD part also offers a substantial memory capacity advantage at 4 GB versus 1 GB, which is a practical benefit for any workload that requires more than a gigabyte of frame buffer. Its higher memory bandwidth of 16.00 GB/s also contributes to its compute performance edge.

The NVIDIA GeForce 825M, however, is not without merit. Its architectural specifications suggest superior texture throughput, with 32 TMUs and a 30.11 GTexel/s texture rate, which is 77% higher than the AMD part. It also has a higher FP32 compute peak of 722.7 GFLOPS and a higher boost clock of 941 MHz. For users who prioritize raw texture fill rates or who have workloads that specifically benefit from NVIDIA's Kepler architecture, the GeForce 825M could be considered, despite its lower benchmark score. Its lower TDP of 33 W also indicates a defined power envelope, though the AMD part's TDP is not disclosed for comparison.

For the majority of users, the choice is clear. The AMD Radeon R5 M420 wins the only available benchmark, offers quadruple the memory capacity, and has a higher memory bandwidth. The NVIDIA part's theoretical advantages in TMUs and FP32 do not translate to a win in the Geekbench OpenCL test, which is the only concrete performance data available. Therefore, the data supports selecting the AMD Radeon R5 M420 for superior overall performance, especially in compute and memory-intensive tasks. The NVIDIA GeForce 825M is only preferable in scenarios where texture fill rate is the absolute bottleneck and where its specific feature set, such as a newer Vulkan version, is required.