AMD Radeon 660M vs NVIDIA Tesla K20Xm Comparison

The NVIDIA Tesla K20Xm and AMD Radeon 660M represent two vastly different eras of GPU design, with the former being a dedicated compute accelerator from 2012 and the latter a modern integrated graphics processor from 2022. The benchmark data reveals a fascinating split between raw compute power and modern API feature support, with each card claiming victories in different areas of performance.

Head-to-Head Benchmarks

The only direct head-to-head benchmark available is Geekbench OpenCL, and the results are decisively in favor of the NVIDIA Tesla K20Xm. The Tesla K20Xm scores 17,215 points, while the AMD Radeon 660M manages 12,876 points. This represents a 33.7% advantage for the NVIDIA card, a substantial margin that underscores the raw compute capability of the older Kepler architecture.

This OpenCL result is particularly telling because it reflects the Tesla K20Xm's design philosophy. With 2,688 shading units and 224 texture mapping units, the K20Xm was built specifically for high-throughput parallel computation. The Radeon 660M, by contrast, is an integrated processor with only 384 shading units and 24 TMUs, making its 12,876 OpenCL score respectable but ultimately dwarfed by the dedicated compute card.

However, the broader benchmark picture shows the Radeon 660M striking back in other areas. The AMD card posts an average benchmark score of 13,812, which is actually higher than the Tesla K20Xm's average of 12,625. This is because the Radeon 660M has additional benchmark results beyond OpenCL, including a Geekbench Vulkan score of 14,748, a test that the Tesla K20Xm cannot run due to its older Vulkan 1.2.175 API support. The K20Xm's only other benchmark is Geekbench Metal at 8,035 points, which drags down its average.

The percentile rankings further illustrate this divide. The Radeon 660M places in the 55th percentile of all GPUs, while the Tesla K20Xm sits at the 52nd percentile. This means that despite losing the OpenCL head-to-head, the Radeon 660M is actually the better-performing card overall when considering all available benchmarks and its superior API compatibility with modern workloads.

FAQ

Q: Which GPU wins in raw OpenCL compute performance?

A: The NVIDIA Tesla K20Xm wins decisively, scoring 17,215 in Geekbench OpenCL compared to the AMD Radeon 660M's 12,876, a 33.7% advantage.

Q: Does the AMD Radeon 660M have any benchmark where it outperforms the Tesla K20Xm?

A: Yes, the Radeon 660M achieves a Geekbench Vulkan score of 14,748, a test the Tesla K20Xm cannot run. This contributes to its higher average benchmark score of 13,812 versus the K20Xm's 12,625.

Q: How do these GPUs compare in terms of overall performance percentile?

A: The AMD Radeon 660M ranks in the 55th percentile of all GPUs, while the NVIDIA Tesla K20Xm ranks in the 52nd percentile, indicating the Radeon is the better overall performer in the full benchmark suite.

Q: What are the closest rivals to each GPU in terms of average benchmark scores?

A: The Tesla K20Xm's closest rival is the AMD Radeon RX 7600M XT with an average score of 12,710 (0.7% higher), while the Radeon 660M's closest rival is the NVIDIA RTX A2000 Mobile with 13,821 (0.1% higher).

Q: Which GPU supports newer graphics APIs?

A: The AMD Radeon 660M supports DirectX 12 Ultimate (12_2) and Vulkan 1.4, while the NVIDIA Tesla K20Xm only supports DirectX 12 (11_0) and Vulkan 1.2.175. The Radeon also supports Vulkan, a test the Tesla cannot run.

Q: What is the memory configuration difference between these two GPUs?

A: The Tesla K20Xm has 6 GB of dedicated GDDR5 memory on a 384-bit bus with 249.6 GB/s bandwidth, while the Radeon 660M uses System Shared memory with bandwidth that is System Dependent.

Where Each One Wins

The NVIDIA Tesla K20Xm is the clear winner for compute-heavy workloads that rely on OpenCL acceleration. Its 33.7% advantage in Geekbench OpenCL demonstrates that the 2,688 shading units and 224 TMUs deliver substantial parallel processing power. This makes it suitable for tasks like scientific computing, data analysis, and any professional application that leverages OpenCL for GPU acceleration. The K20Xm also has dedicated memory with 249.6 GB/s bandwidth, which provides consistent performance without competing with system RAM.

The AMD Radeon 660M wins in modern gaming and graphics applications that utilize Vulkan. Its Geekbench Vulkan score of 14,748 is a strong result, and its DirectX 12 Ultimate (12_2) support means it can handle the latest graphics features and game engines. Additionally, the Radeon 660M has 6 ray tracing cores, a feature entirely absent from the Tesla K20Xm. Its higher overall average benchmark score of 13,812 and 55th percentile ranking indicate that in a mixed workload environment, the Radeon 660M is the more versatile performer.

Specification Differences

The two GPUs differ dramatically in nearly every hardware specification. The Tesla K20Xm uses a 28 nm process node from TSMC, while the Radeon 660M uses a much more advanced 6 nm process from the same foundry. Transistor counts also tell a story: the K20Xm has 7,080 million transistors on a 561 mm² die, while the Radeon 660M has 13,100 million transistors on just 208 mm². This results in a transistor density of 12.6M/mm² for the NVIDIA card versus 63.0M/mm² for the AMD card.

Memory configurations are completely different. The Tesla K20Xm features 6 GB of GDDR5 with a 384-bit bus and 249.6 GB/s bandwidth, while the Radeon 660M uses System Shared memory with no dedicated VRAM. Clock speeds also differ, with the Radeon 660M having a 1500 MHz base clock and 1900 MHz boost clock, while the K20Xm's clock data only lists a memory clock of 1300 MHz (5.2 Gbps effective).

Power requirements are vastly different as well. The Tesla K20Xm has a 235 W TDP and requires a 550 W PSU, while the Radeon 660M has a 40 W TDP and consumes no additional power connectors. The K20Xm is a dual-slot card measuring 267 mm in length, while the Radeon 660M is an IGP with no dimensions listed. The Tesla uses PCIe 3.0 x16, while the Radeon uses PCIe 4.0 x8.

Architecture Differences

The architectural divide between these GPUs is generational. The Tesla K20Xm is built on NVIDIA's Kepler architecture using the GK110 chip, part of the Tesla Kepler (Kxx) generation. It supports DirectX 12 (11_0), OpenGL 4.6, and Vulkan 1.2.175. The K20Xm has no ray tracing cores or tensor cores, reflecting its 2012 design focus on raw FP32 compute.

The AMD Radeon 660M uses the RDNA 2.0 architecture with the Rembrandt chip, part of the Navi II IGP (Rembrandt Mobile) generation. It supports DirectX 12 Ultimate (12_2), OpenGL 4.6, and Vulkan 1.4. Critically, the Radeon 660M includes 6 ray tracing cores, a feature completely missing from the Tesla. The Radeon also supports FP16 compute at 2.918 TFLOPS (2:1 ratio), while the Tesla has no listed FP16 capability.

The production timelines further highlight the architectural gap. The Tesla K20Xm was released on November 11, 2012, with a predecessor of Tesla Fermi and successor of Tesla Maxwell. The Radeon 660M was released on January 3, 2022, with a predecessor of Vega II IGP and successor of Navi III IGP. Both are now end-of-life products, but the Radeon 660M benefits from nearly a decade of architectural advancements.

The Verdict

The data presents a clear choice based on workload priorities. For users who need maximum OpenCL compute performance, the NVIDIA Tesla K20Xm is the superior option, delivering a 33.7% higher score in the head-to-head benchmark. Its dedicated 6 GB of GDDR5 memory and 249.6 GB/s bandwidth ensure consistent throughput without system memory contention. The K20Xm's 52nd percentile ranking and average score of 12,625 place it in a respectable position, though its nearest rivals like the AMD Radeon RX 7600M XT (12,710) and NVIDIA GeForce GTX 670 (12,773) are extremely close.

However, for modern graphics workloads and overall versatility, the AMD Radeon 660M is the better choice. Its Vulkan score of 14,748, support for DirectX 12 Ultimate, and 6 ray tracing cores make it compatible with current gaming and graphics applications. The Radeon 660M's average benchmark score of 13,812 places it in the 55th percentile, and its nearest rival, the NVIDIA RTX A2000 Mobile, is only 0.1% higher at 13,821. The 40 W TDP also makes the Radeon 660M dramatically more power-efficient than the 235 W Tesla, which requires a 550 W PSU and dual-slot cooling.

The choice ultimately comes down to whether the user prioritizes raw OpenCL compute power or modern API support and ray tracing capabilities. The Tesla K20Xm wins where it matters for compute accelerators, while the Radeon 660M wins in every other measurable category. For a professional compute environment using OpenCL, the Tesla K20Xm is the data-supported pick. For gaming, modern applications, or any workload leveraging Vulkan or ray tracing, the Radeon 660M is clearly superior.