AMD Radeon HD 7970M vs NVIDIA T400 Comparison

The AMD Radeon HD 7970M and NVIDIA T400 are both end-of-life graphics solutions, yet they occupy vastly different eras and design philosophies. The HD 7970M is a 2012 mobile flagship built on a 28 nm process with a massive 256-bit memory bus, while the T400 is a 2021 entry-level workstation card on a 12 nm process with a modest 64-bit bus. Despite their differences, their Geekbench OpenCL scores are nearly identical, making this a fascinating comparison of raw compute versus modern efficiency.

FAQ

Q: Which GPU has the higher average benchmark score?

A: The AMD Radeon HD 7970M has a higher average benchmark score of 17,019, while the NVIDIA T400 averages 16,508. However, in the single head-to-head Geekbench OpenCL test, the T400 edges out the HD 7970M by a tiny margin of 20 points (17,039 vs 17,019), a delta of -0.1%.

Q: How do their memory subsystems compare?

A: The AMD Radeon HD 7970M uses 2 GB of GDDR5 on a 256-bit bus, delivering 153.6 GB/s of bandwidth. The NVIDIA T400 also has 2 GB, but it is GDDR6 on a 64-bit bus, providing only 80.00 GB/s—roughly half the bandwidth of the older card.

Q: What are the power consumption differences?

A: The NVIDIA T400 is far more power-efficient, with a 30 W TDP compared to the AMD Radeon HD 7970M's 100 W TDP. The T400 also lists a suggested PSU of 200 W, while the HD 7970M is an MXM module with no power connectors and no suggested PSU listed.

Q: Which card supports newer graphics APIs?

A: The NVIDIA T400 supports DirectX 12 (12_1) and Vulkan 1.4, while the AMD Radeon HD 7970M only reaches DirectX 12 (11_1) and Vulkan 1.2.170. Both support OpenGL 4.6.

Q: How do their compute capabilities differ in terms of shading units?

A: The AMD Radeon HD 7970M has 1,280 shading units, 80 TMUs, and 32 ROPs, while the NVIDIA T400 has just 384 shading units, 24 TMUs, and 16 ROPs. Despite having only a third of the shaders, the T400 nearly matches the HD 7970M in OpenCL performance.

Q: What are the physical form factor differences?

A: The AMD Radeon HD 7970M uses an MXM Module form factor with an MXM-B (3.0) bus interface, making it portable-device dependent. The NVIDIA T400 is a single-slot card with a PCIe 3.0 x16 interface and features 3x mini-DisplayPort 1.4a outputs.

The Verdict

The data presents a clear split based on use case. For users needing maximum raw memory bandwidth and legacy compute throughput, the AMD Radeon HD 7970M holds an edge in texture and pixel fill rates, but its 100 W TDP and portable-device dependency limit its deployment scenarios. The NVIDIA T400, conversely, is the choice for modern workstation environments: it offers a 30 W TDP, a standard PCIe slot, and newer API support (DirectX 12_1, Vulkan 1.4) that the HD 7970M cannot match.

Benchmark results show the T400 wins the only head-to-head test, but the margin is negligible (-0.1%). The real verdict lies in context: the HD 7970M is a relic of high-performance mobile gaming, while the T400 is a low-profile professional card designed for efficiency and compatibility. If you need raw fill rates and have an MXM slot, the HD 7970M is defensible. For nearly any modern desktop workstation, the T400 is the pragmatic pick due to its API support and power profile.

Head-to-Head Benchmarks

The sole head-to-head benchmark is Geekbench OpenCL, where the NVIDIA T400 scores 17,039 against the AMD Radeon HD 7970M's 17,019. This yields a delta of -0.1%, meaning the T400 is just 20 points ahead—a statistically insignificant difference. Both cards land in the 60th percentile among all GPUs, and their nearest rivals reinforce this parity: the HD 7970M sits within 1.1% of the GeForce RTX 3070 and 0.5% of the Tesla M4, while the T400 is within 0.9% of the Radeon RX 5700 XT and 0.6% of both the Radeon PRO W7500 and RTX PRO 6000 Blackwell.

This near-identical OpenCL score is remarkable given the hardware disparity. The HD 7970M has 1,280 shading units and 153.6 GB/s of bandwidth, yet it only barely trails a card with 384 shaders and 80.00 GB/s. The T400 compensates with a 1,425 MHz boost clock versus the HD 7970M's unspecified boost, and its GDDR6 memory runs at 10 Gbps effective versus 4.8 Gbps effective on the HD 7970M. The result is a tie in compute, suggesting that architectural efficiency in the Turing design outweighs the older GCN 1.0's brute-force approach.

Specification Differences

The two cards diverge sharply on nearly every specification. The AMD Radeon HD 7970M uses a 28 nm process with 2,800 million transistors on a 212 mm² die, while the NVIDIA T400 uses a 12 nm process with 4,700 million transistors on a 200 mm² die—yielding a transistor density of 23.5M / mm² versus 13.2M / mm². Memory bandwidth is a major split: 153.6 GB/s on the HD 7970M versus 80.00 GB/s on the T400, despite both having 2 GB. The bus width tells the story: 256-bit for AMD, 64-bit for NVIDIA.

Clock speeds also differ fundamentally. The T400 has a base clock of 420 MHz and a boost of 1,425 MHz, while the HD 7970M lists no base or boost clocks, only a memory clock of 1200 MHz (4.8 Gbps effective). The T400's memory runs at 1250 MHz (10 Gbps effective). Pixel and texture rates favor the HD 7970M: 27.20 GPixel/s and 68.00 GTexel/s versus 22.80 GPixel/s and 34.20 GTexel/s. FP32 compute is nearly double on the AMD card (2.176 TFLOPS vs 1,094.4 GFLOPS), though the T400 offers FP16 at 2.189 TFLOPS.

The TDP difference is stark: 100 W for the HD 7970M versus 30 W for the T400. Form factors diverge with the HD 7970M as an MXM Module and the T400 as a single-slot PCIe card. Display outputs are portable-device dependent on the AMD card, while the T400 has 3x mini-DisplayPort 1.4a.

Architecture Differences

The AMD Radeon HD 7970M is built on GCN 1.0 architecture, a design from 2012 that emphasizes massive parallelism with 1,280 shading units. Its 28 nm process at TSMC yields a die size of 212 mm² and a transistor density of 13.2M / mm². The chip is codenamed Wimbledon and belongs to the London (HD 7900M) generation. The NVIDIA T400, in contrast, uses Turing architecture on a 12 nm process, also at TSMC, but packs 4,700 million transistors into a slightly smaller 200 mm² die, achieving a density of 23.5M / mm². Its chip is TU117, from the Quadro Turing (Tx000) generation.

The shading unit counts reflect this architectural gap: 1,280 on the HD 7970M versus 384 on the T400. Neither card has ray tracing or tensor cores, but the T400's Turing architecture supports DirectX 12 (12_1) and Vulkan 1.4, whereas the HD 7970M's GCN 1.0 is limited to DirectX 12 (11_1) and Vulkan 1.2.170. The T400 also features FP16 compute at 2.189 TFLOPS, which the HD 7970M lacks entirely. The T400's memory is GDDR6 versus GDDR5 on the older card, and its boost clock of 1,425 MHz drives its efficiency.

The architecture differences explain the benchmark parity. Turing's out-of-order execution and modern scheduler allow the T400 to extract more work per shading unit, while GCN 1.0 relies on raw shader count and bandwidth. The HD 7970M's 153.6 GB/s bandwidth feeds its 80 TMUs, but the T400's 34.20 GTexel/s texture rate is sufficient for its intended low-power workstation role.

Where Each One Wins

The AMD Radeon HD 7970M wins on raw throughput metrics. Its pixel rate of 27.20 GPixel/s and texture rate of 68.00 GTexel/s are 19% and 99% higher, respectively, than the T400's 22.80 GPixel/s and 34.20 GTexel/s. Its FP32 compute of 2.176 TFLOPS doubles the T400's 1,094.4 GFLOPS. For workloads that rely on massive parallelism and high memory bandwidth—such as legacy compute tasks or fill-rate-bound rendering—the HD 7970M is superior. Its 256-bit bus and 153.6 GB/s bandwidth are unmatched by the T400's 64-bit bus.

The NVIDIA T400 wins on efficiency and modern feature support. Its 30 W TDP is one-third of the HD 7970M's 100 W, making it deployable in low-power systems. It supports newer APIs—DirectX 12 (12_1) and Vulkan 1.4—which the HD 7970M cannot. The T400 also offers FP16 performance, which is absent on the AMD card. Its 1,425 MHz boost clock and GDDR6 memory at 10 Gbps effective provide a modern baseline for workstation tasks. The T400 also wins the only head-to-head benchmark, albeit by a hair.

In practical terms, the HD 7970M is best suited for older mobile platforms where its MXM form factor fits and where raw bandwidth is king. The T400 is the pick for new builds requiring a low-profile, single-slot card with modern API support and minimal power draw. The benchmark data shows they are equals in OpenCL compute, so the decision hinges on ecosystem fit: the HD 7970M's raw specs versus the T400's architectural modernity.