NVIDIA B300 SXM6 AC vs NVIDIA GeForce RTX 5070 Comparison

NVIDIA B300 SXM6 AC and NVIDIA GeForce RTX 5070 represent two extreme endpoints of the NVIDIA Blackwell family: one is a massive server accelerator built for maximum compute density, the other a dual-slot desktop graphics card aimed at mainstream rendering and gaming. The recorded data shows a single shared benchmark result, the Geekbench OpenCL test, and that comparison is decisive. The B300 SXM6 AC delivers 369,831 points against the RTX 5070's 172,660 points, a 114.2% advantage. This places the server part in a completely different performance tier, as the delta is more than double. The RTX 5070 itself sits at the 82nd percentile of all GPUs in the database, which is a strong result for a consumer card, but the B300 SXM6 AC occupies the 100th percentile, meaning it outperforms every other recorded GPU in the database on this metric.

Head-to-Head Benchmarks

The Geekbench OpenCL score is the only direct comparison available, and it is lopsided. The B300 SXM6 AC's 369,831 score is 114.2% higher than the RTX 5070's 172,660. This is not a marginal win; it is a doubling of raw compute throughput in a synthetic test that heavily exercises parallel processing. In the database, the B300 SXM6 AC's closest rivals are other server accelerators: the NVIDIA B200 scores 345,482 (7% lower), the NVIDIA H200 NVL scores 334,891 (10.4% lower), the AMD Instinct MI300X scores 317,994 (16.3% lower), and the NVIDIA L40S scores 295,763 (25% lower). These deltas show that the B300 SXM6 AC is the top performer in its class, leading the nearest competitor by a meaningful margin. The RTX 5070, by contrast, has a nearest rival group of much lower-performance cards: the AMD Radeon Pro 580 scores 40,318 (0.1% lower), the AMD Radeon Pro WX 7100 scores 40,063 (0.8% lower), the AMD Radeon Pro 5300 scores 40,870 (1.2% higher), and the NVIDIA RTX A500 Mobile scores 39,568 (2% lower). The RTX 5070's average benchmark score across all tests is 40,377, which is its own aggregate metric, but the head-to-head OpenCL result specifically shows the B300 SXM6 AC winning all one comparison in the data (winsA: 1, winsB: 0).

The RTX 5070 has other benchmark results in the database, including 3DMark Steel Nomad DX12 at 5,077, Geekbench Vulkan at 178,923, and Passmark scores across various DirectX versions, with a G3D score of 29,137 and a GPU Compute score of 15,787. None of these have a corresponding B300 SXM6 AC result, so they cannot be compared directly. The B300 SXM6 AC only has the single OpenCL benchmark. The data indicates that for compute-heavy workloads, the server part dominates, but the RTX 5070 has a broader range of tested graphics APIs, including DirectX 12 Ultimate, Vulkan 1.4, and OpenGL 4.6, whereas the B300 SXM6 AC has no recorded API support (DirectX, OpenGL, and Vulkan are all listed as N/A). This suggests the RTX 5070 is designed for interactive graphics, while the B300 SXM6 AC is a compute-only accelerator.

Architecture Differences

The architectural gap between the two is substantial. The B300 SXM6 AC uses the GB110 chip on the Blackwell Ultra architecture, part of the Server Blackwell (Bxx) generation. The RTX 5070 uses the GB205 chip on Blackwell 2.0, part of the GeForce 50 series. Both are fabricated on a 5 nm process at TSMC, but the similarities end there. The B300 SXM6 AC has 208,000 million transistors on a 1628 mm² die, yielding a transistor density of 127.8 million per mm². The RTX 5070 has 31,100 million transistors on a 263 mm² die, with a density of 118.3 million per mm². The server chip is over six times larger in die area and holds nearly seven times the transistor count. This scale difference directly explains the performance gap in compute tests.

The memory subsystems are equally divergent. The B300 SXM6 AC uses 288 GB of HBM3e with an 8192-bit bus, delivering 8.19 TB/s of bandwidth. The RTX 5070 uses 12 GB of GDDR7 with a 192-bit bus, delivering 672.0 GB/s. The server part has 24 times the memory capacity and over 12 times the bandwidth. Clock speeds tell a different story: the RTX 5070 has a higher base clock (2325 MHz vs 1665 MHz) and higher boost clock (2512 MHz vs 2032 MHz). The RTX 5070 also has a higher memory clock at 1750 MHz (28 Gbps effective) versus the B300 SXM6 AC's 2000 MHz (8 Gbps effective), but the effective bandwidth is far lower due to the narrow bus. The B300 SXM6 AC compensates with sheer width and capacity.

Compute resources differ in scale and type. The B300 SXM6 AC has 18,944 shading units, 592 TMUs, and 24 ROPs. The RTX 5070 has 6,144 shading units, 192 TMUs, and 80 ROPs. The server part has roughly three times the shading units and TMUs, but the RTX 5070 has more than three times the ROPs (80 vs 24). The RTX 5070 has 48 dedicated RT cores and 192 tensor cores. The B300 SXM6 AC has no listed RT cores but has 592 tensor cores, which is again roughly three times the count. The B300 SXM6 AC's pixel rate is 48.77 GPixel/s, while the RTX 5070's is 201.0 GPixel/s. The texture rates are 1,202.9 GTexel/s for the server part versus 482.3 GTexel/s for the desktop card. FP32 and FP16 performance are both 76.99 TFLOPS for the B300 SXM6 AC, while the RTX 5070 delivers 30.87 TFLOPS for both. This shows the server part has over 2.5 times the raw floating-point throughput, but the desktop card has a much higher pixel fillrate due to its ROP advantage.

Power and physical design further separate the two. The B300 SXM6 AC is an SXM module with a 1100 W TDP and a suggested power supply of 1500 W. The RTX 5070 is a dual-slot card with a 250 W TDP and a 600 W suggested PSU. The server part has no display outputs, while the RTX 5070 has 1x HDMI 2.1b and 3x DisplayPort 2.1b. The bus interfaces differ as well: the B300 SXM6 AC uses PCIe 6.0 x16, the RTX 5070 uses PCIe 5.0 x16. The RTX 5070 has physical dimensions of 245 mm length, 115 mm height, and 40 mm width, while the B300 SXM6 AC has no recorded dimensions, consistent with its modular form factor.

FAQ

Q: Which GPU is faster in the Geekbench OpenCL test?

A: The NVIDIA B300 SXM6 AC scores 369,831, which is 114.2% higher than the NVIDIA GeForce RTX 5070's 172,660.

Q: Does the RTX 5070 have any advantage in the head-to-head comparison?

A: The recorded data shows the B300 SXM6 AC wins the only direct comparison (winsA: 1, winsB: 0). The RTX 5070 has a higher pixel rate (201.0 GPixel/s vs 48.77 GPixel/s) and more ROPs (80 vs 24), but these are not tested in the head-to-head benchmark.

Q: What is the memory configuration difference?

A: The B300 SXM6 AC has 288 GB of HBM3e with an 8192-bit bus and 8.19 TB/s bandwidth. The RTX 5070 has 12 GB of GDDR7 with a 192-bit bus and 672.0 GB/s bandwidth.

Q: Which GPU has a higher boost clock?

A: The RTX 5070 has a boost clock of 2512 MHz, while the B300 SXM6 AC has a boost clock of 2032 MHz.

Q: Are both GPUs based on the same architecture?

A: No. The B300 SXM6 AC uses Blackwell Ultra (GB110) from the Server Blackwell generation, while the RTX 5070 uses Blackwell 2.0 (GB205) from the GeForce 50 series. Both are on a 5 nm TSMC process.

Q: What is the transistor count difference?

A: The B300 SXM6 AC has 208,000 million transistors on a 1628 mm² die. The RTX 5070 has 31,100 million transistors on a 263 mm² die.

Specification Differences

The two GPUs differ across nearly every recorded specification. The chip designations are GB110 for the B300 SXM6 AC and GB205 for the RTX 5070. The architecture names are Blackwell Ultra versus Blackwell 2.0. The generation identifiers are Server Blackwell (Bxx) versus GeForce 50. The process node is the same at 5 nm, and the foundry is TSMC for both. Transistor counts are 208,000 million versus 31,100 million. Die sizes are 1628 mm² versus 263 mm². Transistor densities are 127.8M per mm² versus 118.3M per mm².

Clock speeds differ: base clocks are 1665 MHz versus 2325 MHz, boost clocks are 2032 MHz versus 2512 MHz. Memory clocks are 2000 MHz (8 Gbps effective) versus 1750 MHz (28 Gbps effective). Memory size is 288 GB versus 12 GB. Memory types are HBM3e versus GDDR7. Bus widths are 8192 bit versus 192 bit. Bandwidth is 8.19 TB/s versus 672.0 GB/s. Shading units are 18,944 versus 6,144. TMUs are 592 versus 192. ROPs are 24 versus 80. RT cores are not listed for the B300 SXM6 AC, while the RTX 5070 has 48. Tensor cores are 592 versus 192. Pixel rates are 48.77 GPixel/s versus 201.0 GPixel/s. Texture rates are 1,202.9 GTexel/s versus 482.3 GTexel/s. FP32 and FP16 are both 76.99 TFLOPS versus 30.87 TFLOPS. TDP is 1100 W versus 250 W. Slot width is SXM Module versus Dual-slot. The B300 SXM6 AC has no power connectors listed, while the RTX 5070 has 1x 16-pin. Suggested PSUs are 1500 W versus 600 W. Bus interfaces are PCIe 6.0 x16 versus PCIe 5.0 x16. Display outputs are none versus 1x HDMI 2.1b and 3x DisplayPort 2.1b. API support is N/A for the B300 SXM6 AC, while the RTX 5070 supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. Dimensions are not recorded for the server part, while the RTX 5070 measures 245 mm by 115 mm by 40 mm. Release dates are September 10, 2025 for the B300 SXM6 AC and March 3, 2025 for the RTX 5070. The B300 SXM6 AC has a launch MSRP of none recorded, while the RTX 5070 has a launch MSRP of 549 USD.

The Verdict

The data positions these two products for entirely different use cases. The NVIDIA B300 SXM6 AC is a server accelerator with no display outputs, no API support, and a TDP of 1100 W. It is designed for compute tasks where raw throughput is paramount. Its Geekbench OpenCL score of 369,831 places it at the 100th percentile of all GPUs in the database, and it leads its nearest rivals by 7% to 25%. The RTX 5070 is a desktop graphics card with display outputs, full API support, and a 250 W TDP. Its average benchmark score of 40,377 places it at the 82nd percentile, and its nearest rivals are within 2% of its score, indicating a crowded mid-range segment.

For workloads that rely on OpenCL compute, the B300 SXM6 AC is the clear choice based on the data. It doubles the RTX 5070's score and has more than twice the FP32 throughput (76.99 TFLOPS vs 30.87 TFLOPS). For interactive graphics, rendering, or any task requiring a display output, the RTX 5070 is the only option between the two, as the B300 SXM6 AC has no display outputs and no API support. The RTX 5070 also has a higher pixel rate (201.0 GPixel/s vs 48.77 GPixel/s) and more ROPs (80 vs 24), which benefits rasterization workloads. The RTX 5070's higher base and boost clocks (2325 MHz and 2512 MHz vs 1665 MHz and 2032 MHz) suggest it can sustain higher frequency operations, but this does not compensate for the B300 SXM6 AC's massive memory bandwidth (8.19 TB/s vs 672.0 GB/s) and larger memory pool (288 GB vs 12 GB). The data indicates the server part is for large-scale compute and AI training, while the desktop card is for consumer graphics. Neither product serves the other's intended function.