AMD Radeon RX 6600S vs NVIDIA Tesla K20Xm Comparison

Head-to-Head Benchmarks

The only directly comparable measurement in the database is Geekbench OpenCL, and the result is a decisive sweep for the AMD Radeon RX 6600S. The RX 6600S scores 66,435 points, while the NVIDIA Tesla K20Xm scores 17,215 points. That works out to a 74.1% deficit for the Tesla, meaning the AMD part delivers roughly 3.9 times the OpenCL compute throughput in this test. The delta is so large that it is not a close contest; the RX 6600S is in a different performance class for this workload.

The Tesla K20Xm also has a Geekbench Metal score of 8,035, but the RX 6600S has no Metal benchmark recorded, so no direct comparison exists there. On the PassMark suite, the RX 6600S posts scores of 12,649 in G3D, 4,879 in GPU Compute, 647 in G2D, 176 in DirectX 9, 105 in DirectX 11, 81 in DirectX 10, and 56 in DirectX 12. The Tesla has no PassMark entries at all, so those results stand only for the AMD card.

In terms of overall average benchmark score, the Tesla K20Xm lands at 12,625, while the RX 6600S averages 10,629. That is a 15.8% gap favoring the older NVIDIA card when averaging across all recorded tests, but that figure is skewed by the different test sets available for each GPU. The Tesla’s two OpenCL and Metal results are both high, while the AMD card’s average includes several low PassMark legacy DirectX scores that drag it down. The head-to-head OpenCL result is the cleanest apples-to-apples comparison, and it heavily favors AMD.

Architecture Differences

The Tesla K20Xm is built on NVIDIA’s Kepler architecture, using the GK110 chip fabricated on a 28 nm process at TSMC. It packs 7,080 million transistors on a 561 mm² die, giving a transistor density of 12.6 million per square millimeter. The RX 6600S uses AMD’s RDNA 2.0 architecture, with the Navi 23 chip on a 7 nm process, also at TSMC. Navi 23 contains 11,060 million transistors on a much smaller 237 mm² die, yielding a density of 46.7 million per square millimeter. That is nearly 3.7 times the transistor density of the Kepler part, a direct consequence of the newer process node.

The Tesla is a dual-slot compute card with no display outputs, designed for server or workstation compute duty. Its memory runs at 1300 MHz, or 5.2 Gbps effective, across a 384-bit bus, feeding 6 GB of GDDR5. Bandwidth is 249.6 GB/s. The RX 6600S is a mobile integrated GPU (IGP) with no dedicated power connectors, and its display outputs are described as portable device dependent. It uses 4 GB of GDDR6 on a 128-bit bus, with memory at 1750 MHz, or 14 Gbps effective, for 224.0 GB/s of bandwidth. The AMD card has a smaller bus and less memory, but faster memory speed narrows the bandwidth gap to about 10.3% in favor of the Tesla.

The Tesla has 2,688 shading units, 224 texture mapping units, and 48 ROPs. The RX 6600S has 1,792 shading units, 112 TMUs, and 64 ROPs. The AMD card has fewer shaders and TMUs but more ROPs. The RX 6600S also includes 28 ray tracing cores, while the Tesla has none. Neither card has tensor cores. The Tesla’s pixel rate is 40.99 GPixel/s and its texture rate is 164.0 GTexel/s. The RX 6600S posts a pixel rate of 128.0 GPixel/s and a texture rate of 224.0 GTexel/s, meaning the AMD part is 3.1 times faster in pixel throughput and 36.6% faster in texture throughput.

FP32 compute tells a similar story: the Tesla delivers 3.935 TFLOPS, while the RX 6600S delivers 7.168 TFLOPS, an 82.2% advantage for AMD. The RX 6600S also supports FP16 at 14.34 TFLOPS (2:1 ratio), while the Tesla has no recorded FP16 capability. The Tesla’s TDP is 235 W with a suggested 550 W PSU, while the RX 6600S draws only 80 W and has no suggested PSU listed. That is a 155 W difference, or a 65.9% reduction in power draw for the AMD card.

Where Each One Wins

The RX 6600S wins the only shared benchmark, Geekbench OpenCL, by an enormous margin. It also wins on raw compute metrics: FP32, pixel rate, texture rate, and it has ray tracing support that the Tesla lacks. For any modern workload that leverages RDNA 2 features, DirectX 12 Ultimate, or FP16 compute, the RX 6600S is the clear choice. Its 7 nm process and 80 W TDP make it far more efficient per watt, and its PCIe 4.0 x8 interface offers double the per-lane bandwidth of the Tesla’s PCIe 3.0 x16.

The Tesla K20Xm wins on memory bandwidth, with 249.6 GB/s versus 224.0 GB/s, a 10.2% lead. It also has 50% more memory capacity (6 GB versus 4 GB), which matters for datasets that exceed 4 GB. Its 384-bit bus provides a wider memory path, and its 2,688 shading units outnumber the AMD card’s 1,792. In the database’s average benchmark score, the Tesla comes out ahead at 12,625 versus 10,629, though that is partly due to the different test sets. The Tesla also has a higher percentile rank among all GPUs: 52nd percentile versus 49th for the RX 6600S.

For legacy compute tasks that rely on Kepler’s particular strengths, such as double-precision or large memory buffers, the Tesla’s 6 GB frame buffer and higher bandwidth are advantages. But the RX 6600S dominates in every modern compute and graphics metric recorded, and it does so at a fraction of the power draw. The Tesla is an end-of-life product from 2012, while the RX 6600S launched in early 2022, so the architectural gap is expected.

Specification Differences

The two cards differ on nearly every specification in the database. The Tesla uses 28 nm, the RX 6600S uses 7 nm. Transistor count is 7,080 million versus 11,060 million, and die size is 561 mm² versus 237 mm². The Tesla has a base clock listed as null, while the RX 6600S has a base clock of 1700 MHz, a boost clock of 2000 MHz, and a game clock of 1881 MHz. Memory type is GDDR5 versus GDDR6, bus width is 384-bit versus 128-bit, and memory size is 6 GB versus 4 GB.

Shading units: 2,688 versus 1,792. TMUs: 224 versus 112. ROPs: 48 versus 64. The RX 6600S has 28 ray tracing cores; the Tesla has none. FP32: 3.935 TFLOPS versus 7.168 TFLOPS. FP16: null versus 14.34 TFLOPS. TDP: 235 W versus 80 W. Slot width: dual-slot versus IGP. Power connectors: null versus none. Suggested PSU: 550 W versus null. Bus interface: PCIe 3.0 x16 versus PCIe 4.0 x8.

The Tesla has no display outputs; the RX 6600S has portable device dependent outputs. The Tesla’s DirectX support is 12 (11_0), while the RX 6600S supports DirectX 12 Ultimate (12_2). OpenGL is 4.6 for both. Vulkan versions differ: 1.2.175 for the Tesla, 1.4 for the RX 6600S. The Tesla’s dimensions are 267 mm in length, while the RX 6600S has no recorded dimensions. Release dates are 2012-11-11 for the Tesla and 2022-01-03 for the RX 6600S. The Tesla’s launch MSRP was 7,699 USD, while the RX 6600S has no launch MSRP recorded.

FAQ

Q: Which GPU has higher raw FP32 compute?

A: The AMD Radeon RX 6600S, at 7.168 TFLOPS compared to the NVIDIA Tesla K20Xm’s 3.935 TFLOPS, a 82.2% advantage.

Q: Does the Tesla K20Xm support ray tracing?

A: No. The Tesla has no ray tracing cores, while the RX 6600S includes 28 ray tracing cores.

Q: Which card has more memory and bandwidth?

A: The Tesla K20Xm has 6 GB of GDDR5 on a 384-bit bus with 249.6 GB/s bandwidth. The RX 6600S has 4 GB of GDDR6 on a 128-bit bus with 224.0 GB/s bandwidth.

Q: How do their power requirements compare?

A: The Tesla is rated at 235 W TDP with a suggested 550 W PSU. The RX 6600S is rated at 80 W TDP and has no suggested PSU listed, meaning it draws far less power.

Q: What is the DirectX support difference?

A: The Tesla supports DirectX 12 (11_0), while the RX 6600S supports DirectX 12 Ultimate (12_2), which includes newer features.

Q: Which card has a higher average benchmark score?

A: The Tesla K20Xm averages 12,625 across its recorded tests, while the RX 6600S averages 10,629. However, the only shared test, Geekbench OpenCL, heavily favors the RX 6600S.

The Verdict

The AMD Radeon RX 6600S is the better choice for anyone running modern compute or graphics workloads. It wins the only direct head-to-head benchmark by 74.1%, delivers nearly double the FP32 throughput, has ray tracing support, and consumes 155 W less power. Its 7 nm process and newer architecture make it far more efficient, and its DirectX 12 Ultimate and Vulkan 1.4 support mean it can handle current software standards. The mobile form factor with no power connectors also makes it suitable for laptops or compact systems.

The NVIDIA Tesla K20Xm retains a narrow edge in memory bandwidth and capacity, which could matter for workloads that need more than 4 GB of video memory or benefit from a wider memory bus. Its higher average benchmark score (12,625 versus 10,629) and 52nd percentile ranking versus 49th for the AMD card reflect that it holds up in legacy compute tests. But that advantage comes from a different test set, not from superior performance in any shared measurement.

For a builder choosing between these two today, the RX 6600S is the practical pick. It is faster, cooler, smaller, and newer. The Tesla K20Xm is an end-of-life compute card with no display outputs, a dual-slot footprint, and a 7,699 USD launch MSRP that reflects its enterprise origins. Unless a specific workload requires 6 GB of memory on a 384-bit bus, the data points almost entirely to the AMD part. The RX 6600S wins the one benchmark that matters, and its architectural advantages across the board make the verdict straightforward.