AMD Radeon RX 6400 vs NVIDIA GeForce GTX 675M Comparison

Head-to-Head Benchmarks

The database contains a single direct benchmark comparison between these two GPUs, and the result is a decisive victory for the AMD Radeon RX 6400. In the Geekbench OpenCL test, the RX 6400 scores 32,011 points, while the NVIDIA GeForce GTX 675M manages 6,946 points. That translates to an 78.3% lead for the AMD card, a massive gap that reflects the generational chasm between the two products.

To put the GTX 675M’s score in context, it sits at the 39th percentile of all GPUs in the database. Its closest rivals are the AMD Radeon R5 M240 (6,975 points, 0.4% ahead), the NVIDIA GeForce GTX 680M (7,023 points, 1.1% ahead), the NVIDIA T600 (7,035 points, 1.3% ahead), and the AMD FirePro M5100 (6,830 points, 1.7% behind). The GTX 675M is effectively in a tight cluster of mid-range mobile parts from roughly the same era, with all four rivals within a 3% band.

The RX 6400, by contrast, sits at the 35th percentile overall, which is lower than the GTX 675M’s percentile despite a far higher raw score. This is because the RX 6400 is being compared against a much larger and more modern GPU pool, including many high-end desktop cards. Its immediate rivals are the NVIDIA GeForce GTX 770M (6,000 points, 0% delta), the NVIDIA RTX PRO 6000 Blackwell Server (5,996 points, 0.1% ahead), the AMD FirePro W4100 (5,987 points, 0.2% ahead), and the NVIDIA Quadro K4000M (5,986 points, 0.3% ahead). These are all far weaker in absolute terms, yet the RX 6400’s average benchmark score of 6,001 is dragged down by its other test results. The OpenCL score of 32,011 is the outlier, while its Passmark G3D score of 7,673 and Passmark G2D score of 722 tell a more modest story. In the single head-to-head test, the RX 6400 wins outright, and the data shows no benchmark where the GTX 675M comes out ahead.

Architecture Differences

The two GPUs come from completely different design eras. The GTX 675M uses NVIDIA’s GF114 chip, built on the Fermi 2.0 architecture, fabricated by TSMC on a 40 nm process. It packs 1,950 million transistors into a 332 mm² die, giving a transistor density of 5.9 million per square millimeter. The RX 6400, in contrast, uses AMD’s Navi 24 chip, based on RDNA 2.0, also fabricated by TSMC but on a 6 nm process. It contains 5,400 million transistors in a much smaller 107 mm² die, yielding a transistor density of 50.5 million per square millimeter. That is a 9x improvement in density, enabled by the move from 40 nm to 6 nm lithography.

The shader configuration differs substantially. The GTX 675M has 384 shading units, 64 texture mapping units, and 32 ROPs. The RX 6400 doubles the shader count to 768, but reduces TMUs to 48 while keeping 32 ROPs. The RX 6400 also introduces 12 ray tracing cores, a feature entirely absent from the Fermi architecture. The GTX 675M’s pixel rate is 9.920 GPixel/s and its texture rate is 39.68 GTexel/s, while the RX 6400 reaches 74.27 GPixel/s and 111.4 GTexel/s. In raw FP32 compute, the RX 6400 delivers 3.565 TFLOPS versus 952.3 GFLOPS for the GTX 675M, a near 4x advantage. The RX 6400 also supports FP16 at 7.130 TFLOPS (2:1 ratio), while the GTX 675M has no FP16 figure recorded.

Memory architecture is another major divider. The GTX 675M uses 2 GB of GDDR5 on a 256-bit bus, with a memory clock of 750 MHz (3 Gbps effective) and bandwidth of 96.00 GB/s. The RX 6400 has 4 GB of GDDR6 on a 64-bit bus, with a memory clock of 2000 MHz (16 Gbps effective) and bandwidth of 128.0 GB/s. Despite the narrower bus, the faster GDDR6 memory gives the RX 6400 a 33% bandwidth advantage. The GTX 675M’s clock speeds are not fully recorded in the database, with only the memory clock listed. The RX 6400 has a base clock of 1923 MHz, a boost clock of 2321 MHz, and a game clock of 2039 MHz.

API support also differs. The GTX 675M supports DirectX 12 (11_0) and OpenGL 4.6, but has no Vulkan entry. The RX 6400 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. The RX 6400’s feature set is far more modern, including hardware ray tracing and variable rate shading capabilities inherent to RDNA 2.0, though the database does not list those specific features beyond the RT core count.

FAQ

Q: Which GPU has a higher raw compute performance?

A: The AMD Radeon RX 6400 delivers 3.565 TFLOPS in FP32, while the NVIDIA GeForce GTX 675M manages 952.3 GFLOPS. The RX 6400 is roughly 3.7x faster in this metric.

Q: How do the memory subsystems compare?

A: The GTX 675M has 2 GB of GDDR5 on a 256-bit bus with 96.00 GB/s bandwidth. The RX 6400 has 4 GB of GDDR6 on a 64-bit bus with 128.0 GB/s bandwidth. The RX 6400 offers both more capacity and higher bandwidth.

Q: What is the performance gap in the only shared benchmark?

A: In Geekbench OpenCL, the RX 6400 scores 32,011 versus 6,946 for the GTX 675M, a 78.3% difference in favor of the AMD card.

Q: Which GPU supports ray tracing?

A: The AMD Radeon RX 6400 has 12 ray tracing cores. The NVIDIA GeForce GTX 675M has no ray tracing cores listed in the database.

Q: How do the process nodes compare?

A: The GTX 675M is built on TSMC’s 40 nm process, while the RX 6400 uses TSMC’s 6 nm process. The RX 6400 achieves a transistor density of 50.5M per mm² versus 5.9M per mm² for the GTX 675M.

Q: What are the power requirements?

A: The GTX 675M has a TDP of 100 W and uses an MXM module slot. The RX 6400 has a TDP of 53 W, is a single-slot card, and has a suggested PSU of 250 W. Neither requires external power connectors.

Specification Differences

| Specification | NVIDIA GeForce GTX 675M | AMD Radeon RX 6400 |

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

| Chip | GF114 | Navi 24 |

| Architecture | Fermi 2.0 | RDNA 2.0 |

| Process Node | 40 nm | 6 nm |

| Transistors | 1,950 million | 5,400 million |

| Die Size | 332 mm² | 107 mm² |

| Transistor Density | 5.9M / mm² | 50.5M / mm² |

| Base Clock | Not listed | 1923 MHz |

| Boost Clock | Not listed | 2321 MHz |

| Game Clock | Not listed | 2039 MHz |

| Memory Clock | 750 MHz (3 Gbps effective) | 2000 MHz (16 Gbps effective) |

| Memory Size | 2 GB | 4 GB |

| Memory Type | GDDR5 | GDDR6 |

| Memory Bus Width | 256 bit | 64 bit |

| Memory Bandwidth | 96.00 GB/s | 128.0 GB/s |

| Shading Units | 384 | 768 |

| TMUs | 64 | 48 |

| ROPs | 32 | 32 |

| RT Cores | Not listed | 12 |

| Pixel Rate | 9.920 GPixel/s | 74.27 GPixel/s |

| Texture Rate | 39.68 GTexel/s | 111.4 GTexel/s |

| FP32 | 952.3 GFLOPS | 3.565 TFLOPS |

| FP16 | Not listed | 7.130 TFLOPS (2:1) |

| TDP | 100 W | 53 W |

| Slot Width | MXM Module | Single-slot |

| Bus Interface | MXM-B (3.0) | PCIe 4.0 x4 |

| Display Outputs | Portable Device Dependent | 1x HDMI 2.1, 1x DisplayPort 1.4a |

| DirectX | 12 (11_0) | 12 Ultimate (12_2) |

| Vulkan | Not listed | 1.4 |

| Release Date | 2012-03-21 | 2022-01-18 |

| Production Status | End-of-life | End-of-life |

| Launch MSRP | Not listed | 159 USD |

Where Each One Wins

The AMD Radeon RX 6400 wins decisively in every measured category except for one: the GTX 675M holds a higher percentile ranking (39th versus 35th) and a higher average benchmark score relative to its immediate rivals. But that is a quirk of the comparison pool, not a real performance advantage. The RX 6400’s OpenCL score is 4.6x higher, its FP32 compute is 3.7x higher, its pixel rate is 7.5x higher, and its texture rate is 2.8x higher. It also offers double the memory capacity, higher bandwidth, modern API support including Vulkan 1.4 and DirectX 12 Ultimate, and hardware ray tracing.

For gaming and modern workloads, the RX 6400 is the clear choice. The 4 GB GDDR6 frame buffer and 128.0 GB/s bandwidth handle current titles far better than the GTX 675M’s 2 GB GDDR5 setup. The 12 RT cores enable ray-traced effects that the Fermi architecture cannot process at all. The lower 53 W TDP also means it can be deployed in compact single-slot systems with a modest 250 W PSU, whereas the GTX 675M requires a portable device with MXM module support and consumes nearly double the power.

The GTX 675M retains relevance only in legacy scenarios. Its 256-bit memory bus, while paired with slower GDDR5, provides a wider path that some older workloads may favor, though the database shows no benchmark where it outperforms the RX 6400. Its MXM-B (3.0) form factor makes it a drop-in upgrade for certain mobile workstations from the early 2010s, and its 100 W TDP is manageable in those systems. The GTX 675M’s 39th percentile ranking also indicates it sits closer to the median of all GPUs in the database, but this is due to the RX 6400 being compared against a more crowded modern field.

In practical terms, the RX 6400 is the superior part for any contemporary use case. The 78.3% OpenCL gap is the single most telling metric: it is not a close contest, and no benchmark in the database suggests the GTX 675M can close that divide. The GTX 675M is a product of its era, and the data reflects that. For users seeking maximum compatibility with modern APIs, higher compute throughput, and efficient power draw, the RX 6400 is the only rational pick.