AMD Radeon R5 M420 vs NVIDIA GeForce RTX 3080 12 GB Comparison

The Verdict

The data presents a stark contrast between two GPUs separated by six years of silicon evolution. The AMD Radeon R5 M420, an integrated-class part from the GCN 1.0 era, and the NVIDIA GeForce RTX 3080 12 GB, a discrete Ampere flagship, occupy entirely different performance tiers. Benchmark results show the RTX 3080 12 GB achieving a score of 4791 in the 3DMark Steel Nomad DX12 test, while the R5 M420 manages 3956 in Geekbench OpenCL. These are different workloads, but the architectural gulf is unmistakable.

For users constrained to a portable device with the R5 M420, the data indicates this is a legacy component, end-of-life, suitable only for basic display output and light 2D tasks. The RTX 3080 12 GB, despite being end-of-life itself, remains a high-end discrete solution with dedicated ray tracing cores and tensor cores. The recorded data shows the RTX 3080 12 GB sits at the 28th percentile among all GPUs, while the R5 M420 sits at the 23rd percentile, but those percentiles reflect different benchmark pools and should not be read as comparable. The RTX 3080 12 GB is the clear choice for any compute-intensive or gaming workload, while the R5 M420 has no scenario in this data where it wins a head-to-head comparison. Users should choose the RTX 3080 12 GB unless their system physically cannot accommodate a dual-slot, 285 mm discrete card.

Architecture Differences

The R5 M420 uses the Jet chip built on GCN 1.0 architecture, manufactured on a 28 nm process at TSMC. It contains 690 million transistors on a 56 mm² die, yielding a transistor density of 12.3 million per square millimeter. The RTX 3080 12 GB uses the GA102 chip on Ampere architecture, built on an 8 nm process at Samsung. It packs 28,300 million transistors onto a 628 mm² die, achieving a density of 45.1 million per square millimeter. The density difference is nearly fourfold, reflecting the newer process and more complex design.

The R5 M420 ships with 320 shading units, 20 texture mapping units, and 8 raster output units. It has no dedicated ray tracing or tensor cores. The RTX 3080 12 GB carries 8960 shading units, 280 TMUs, and 96 ROPs, plus 70 RT cores and 280 tensor cores. The raw compute resources are an order of magnitude larger across every category.

Memory architecture diverges completely. The R5 M420 uses 4 GB of DDR3 on a 64-bit bus, delivering 16.00 GB/s of bandwidth. The RTX 3080 12 GB uses 12 GB of GDDR6X on a 384-bit bus, delivering 912.4 GB/s. That is a 57x difference in memory bandwidth. Clock speeds also differ substantially: the R5 M420 runs at a base of 780 MHz and boost of 850 MHz, while the RTX 3080 12 GB runs at 1260 MHz base and 1710 MHz boost. The memory clock on the RTX 3080 12 GB is 1188 MHz with 19 Gbps effective data rate, versus 1000 MHz and 2 Gbps effective on the R5 M420.

API support reflects the generational gap. The R5 M420 supports DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.170. The RTX 3080 12 GB supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The newer API levels on the RTX 3080 12 GB enable hardware-accelerated ray tracing and mesh shaders, features entirely absent from the older part.

Where Each One Wins

The benchmark data shows the R5 M420 does not win any recorded comparison against the RTX 3080 12 GB. The head-to-head benchmark list is empty, and the wins counters show zero for both sides, meaning no direct comparison exists in the database. The R5 M420's only recorded benchmark is Geekbench OpenCL at 3956, which places it alongside the NVIDIA GeForce 830M (3957, 0% delta), the NVIDIA GeForce GT 745M (3953, 0.1% delta), the NVIDIA Quadro K2000 (3964, -0.2% delta), and the AMD Radeon HD 6850 X2 (3977, -0.5% delta). These are all low-end or older parts, confirming the R5 M420's position at the entry level.

The RTX 3080 12 GB's recorded benchmark is 3DMark Steel Nomad DX12 at 4791. Its nearest rivals in the database are the AMD Radeon R5 M255 (4788, 0.1% delta), the AMD Radeon R5 M335 (4752, 0.8% delta), the NVIDIA GeForce 940MX (4844, -1.1% delta), and the NVIDIA GeForce GTX 560M (4855, -1.3% delta). This is a peculiar grouping, as these rivals are all low-end mobile or older parts, suggesting the Steel Nomad test is not the RTX 3080 12 GB's strongest showcase. Nevertheless, the RTX 3080 12 GB's strengths lie in its massive memory bandwidth, high FP32 throughput of 30.64 TFLOPS, and dedicated RT and tensor cores, which make it suitable for ray-traced gaming, machine learning inference, and high-resolution rendering. The R5 M420, with its 544.0 GFLOPS FP32 and 16.00 GB/s bandwidth, is only viable for basic desktop composition and legacy software.

FAQ

Q: Which GPU has higher raw compute performance?

A: The RTX 3080 12 GB delivers 30.64 TFLOPS of FP32 compute, while the R5 M420 delivers 544.0 GFLOPS. The RTX 3080 12 GB is approximately 56 times faster in raw FP32 throughput.

Q: Do both GPUs support ray tracing?

A: No. The RTX 3080 12 GB has 70 dedicated RT cores and supports DirectX 12 Ultimate (12_2), which includes ray tracing features. The R5 M420 has no RT cores and only supports DirectX 12 (11_1).

Q: How do their memory systems compare?

A: The R5 M420 uses 4 GB of DDR3 on a 64-bit bus with 16.00 GB/s bandwidth. The RTX 3080 12 GB uses 12 GB of GDDR6X on a 384-bit bus with 912.4 GB/s bandwidth, a 57x bandwidth advantage.

Q: What is the physical footprint difference?

A: The R5 M420 is an IGP (integrated graphics processor) with no separate dimensions listed, dependent on the portable device. The RTX 3080 12 GB is a dual-slot card measuring 285 mm in length, 112 mm in height, and 40 mm in width, requiring a 12-pin power connector and a suggested 750 W power supply.

Q: Which GPU is newer?

A: The R5 M420 was released on May 14, 2016. The RTX 3080 12 GB was released on January 10, 2022, nearly six years later.

Q: Are either of these GPUs still in production?

A: No. Both are listed as end-of-life in the database.

Head-to-Head Benchmarks

The database contains no direct head-to-head benchmark results between the R5 M420 and the RTX 3080 12 GB. The wins counters are zero for both, confirming that no shared test has been recorded. However, the individual benchmarks provide context. The R5 M420 scores 3956 in Geekbench OpenCL, a test that measures general-purpose compute performance. Its nearest rival is the NVIDIA GeForce 830M at 3957, a virtual tie (0% delta). The RTX 3080 12 GB scores 4791 in 3DMark Steel Nomad DX12, a modern gaming-oriented workload. Its nearest rival is the AMD Radeon R5 M255 at 4788, with the RTX 3080 12 GB ahead by 0.1%.

The discrepancy between the GPU's class and its nearest rivals in the RTX 3080 12 GB's case deserves scrutiny. The RTX 3080 12 GB, a top-tier Ampere card, is listed alongside the GeForce 940MX and GeForce GTX 560M in this particular test. This suggests the Steel Nomad workload may be heavily CPU-bound or resolution-limited in the database's testing methodology, or the test itself is not scaling with the RTX 3080 12 GB's full capabilities. In contrast, the R5 M420's rivals are all in its expected performance class. The data indicates that while the RTX 3080 12 GB achieves a higher absolute score, its measured delta over its nearest rivals is modest (0.1% to 0.8% ahead, or 1.1% to 1.3% behind the GeForce 940MX and GTX 560M), which is unusual for a card of its specifications.

The pixel rate and texture rate tell a clearer story. The R5 M420 produces 6.800 GPixel/s and 17.00 GTexel/s. The RTX 3080 12 GB produces 164.2 GPixel/s and 478.8 GTexel/s. These are 24x and 28x differences, respectively. The RTX 3080 12 GB's FP32 throughput of 30.64 TFLOPS dwarfs the R5 M420's 544.0 GFLOPS. The RTX 3080 12 GB also has FP16 performance at a 1:1 ratio with FP32, while the R5 M420 has no recorded FP16 capability. For any workload that can leverage these resources, the RTX 3080 12 GB is in a different universe.

Specification Differences

The two GPUs differ in nearly every measurable specification. The R5 M420 is built on a 28 nm process, the RTX 3080 12 GB on 8 nm. Transistor count is 690 million versus 28,300 million. Die size is 56 mm² versus 628 mm². Transistor density is 12.3M/mm² versus 45.1M/mm². The R5 M420 has no series designation; the RTX 3080 12 GB is part of the GeForce 30-series.

Clock speeds: the R5 M420 runs at 780 MHz base and 850 MHz boost, with memory at 1000 MHz (2 Gbps effective). The RTX 3080 12 GB runs at 1260 MHz base and 1710 MHz boost, with memory at 1188 MHz (19 Gbps effective).

Memory: the R5 M420 has 4 GB DDR3 on a 64-bit bus with 16.00 GB/s bandwidth. The RTX 3080 12 GB has 12 GB GDDR6X on a 384-bit bus with 912.4 GB/s bandwidth.

Compute units: the R5 M420 has 320 shading units, 20 TMUs, and 8 ROPs. The RTX 3080 12 GB has 8960 shading units, 280 TMUs, and 96 ROPs, plus 70 RT cores and 280 tensor cores.

Output rates: the R5 M420 achieves 6.800 GPixel/s and 17.00 GTexel/s. The RTX 3080 12 GB achieves 164.2 GPixel/s and 478.8 GTexel/s. FP32 is 544.0 GFLOPS versus 30.64 TFLOPS. The RTX 3080 12 GB also has FP16 at 30.64 TFLOPS; the R5 M420 has no FP16 figure.

Power and physical: the R5 M420 is an IGP with no TDP listed, no power connectors, and no dimensions. The RTX 3080 12 GB has a 350 W TDP, a dual-slot form factor, one 12-pin power connector, a suggested 750 W power supply, and measures 285 mm by 112 mm by 40 mm.

Bus and outputs: the R5 M420 uses PCIe 3.0 x8 and has portable-device-dependent display outputs. The RTX 3080 12 GB uses PCIe 4.0 x16 and has 1x HDMI 2.1 plus 3x DisplayPort 1.4a.

APIs: the R5 M420 supports DirectX 12 (11_1), OpenGL 4.6, and Vulkan 1.2.170. The RTX 3080 12 GB supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4.

Release and lifecycle: the R5 M420 launched May 14, 2016, with the predecessor Solar System and successor Polaris Mobile. The RTX 3080 12 GB launched January 10, 2022, with the predecessor GeForce 20 and successor GeForce 40. Both are end-of-life. The RTX 3080 12 GB has a recorded launch MSRP of 799 USD; the R5 M420 has no launch MSRP recorded.