GPU Comparison

The NVIDIA GRID K2 and AMD Radeon HD 8850M are both end-of-life products from 2013, but they occupy entirely different segments of the GPU market. The GRID K2 is a dual-slot, 225 W server-oriented accelerator with no display outputs, while the HD 8850M is a mobile chip designed for laptops. The benchmark data shows a clear performance hierarchy, but the architectural and feature differences are what truly define their respective use cases.

Where Each One Wins

The data is unambiguous regarding raw compute performance. In the only head-to-head benchmark available, Geekbench OpenCL, the NVIDIA GRID K2 scores 10,602 points, while the AMD Radeon HD 8850M scores 7,447 points. This translates to a 42.4% delta in favor of the NVIDIA part, which is a substantial margin for any comparison.

This makes the GRID K2 the clear winner in any workload that leverages OpenCL compute. Its shading units, texture units, and memory bandwidth are all significantly higher than the AMD part. The GRID K2 has 1,536 shading units, 128 TMUs, and 32 ROPs, versus the HD 8850M’s 640 shading units, 40 TMUs, and 16 ROPs. The GRID K2’s fill rates are also dominant: 23.84 GPixel/s pixel rate and 95.36 GTexel/s texture rate, against the HD 8850M’s 10.00 GPixel/s and 25.00 GTexel/s.

However, the AMD Radeon HD 8850M is not without its own wins, even if they are not reflected in the benchmark scores. As a mobile GPU, it is designed for integration into laptops, which the GRID K2 simply cannot do, given its 267 mm length, dual-slot design, and 1x 6-pin + 1x 8-pin power connector requirement. The HD 8850M also supports a slightly higher DirectX feature level, with DirectX 12 (11_1) versus the GRID K2’s DirectX 12 (11_0). In a purely mobile context, the HD 8850M wins by existing where the GRID K2 cannot.

The GRID K2 also wins on API support in one area: Vulkan. It supports Vulkan 1.2.175, while the HD 8850M supports Vulkan 1.2.170. Both support OpenGL 4.6, so there is no differentiation there.

Architecture Differences

The two GPUs are built on the same 28 nm process node at TSMC, but their internal architectures are fundamentally different. The NVIDIA GRID K2 uses the GK104 chip, which is based on the Kepler architecture. The AMD Radeon HD 8850M uses the Venus chip, based on the Graphics Core Next (GCN) 1.0 architecture.

The transistor counts and die sizes reflect the performance gulf. The GRID K2 packs 3,540 million transistors into a 294 mm² die, resulting in a transistor density of 12.0M / mm². The HD 8850M has 1,500 million transistors on a much smaller 123 mm² die, with a similar density of 12.2M / mm². The GRID K2’s die is nearly 2.4 times larger, which is consistent with its much higher compute throughput.

Memory configurations also differ sharply. The GRID K2 comes with 4 GB of GDDR5 memory on a 256-bit bus, delivering 160.0 GB/s of bandwidth. The HD 8850M has 2 GB of GDDR5 on a 128-bit bus, yielding just 64.00 GB/s. This is a 2.5x advantage in memory bandwidth for the NVIDIA part, which is critical for memory-bound compute workloads.

Clock speeds tell a different story. The HD 8850M has a base clock of 575 MHz and a boost clock of 625 MHz. The GRID K2’s base and boost clocks are not listed in the data, but its memory clock is 1250 MHz (5 Gbps effective). The HD 8850M’s memory clock is 1000 MHz (4 Gbps effective). Despite the lower core clock, the GRID K2’s massive core count gives it a 2.289 TFLOPS FP32 throughput, versus the HD 8850M’s 800.0 GFLOPS.

The power and physical profiles could not be more different. The GRID K2 has a 225 W TDP, while the HD 8850M has no listed TDP, which is typical for a mobile part where thermal design is more flexible. The GRID K2 requires a 550 W suggested PSU and dual-slot cooling. The HD 8850M has no such requirements listed, reinforcing its mobile nature. Both use PCIe 3.0 x16 interfaces.

The Verdict

The verdict is straightforward when looking strictly at benchmark performance. The NVIDIA GRID K2 is the superior compute device by a wide margin, with a 42.4% lead in OpenCL over the AMD Radeon HD 8850M. Its higher average benchmark score of 8,080 versus 7,447 places it in the 42nd percentile of all GPUs, while the HD 8850M sits in the 40th percentile.

The GRID K2’s nearest rivals in the database are all desktop or high-end mobile parts: the NVIDIA GeForce GTX 650 Ti Boost (8,067 average score, 0.2% delta), the NVIDIA GeForce 945M (8,099, -0.2%), the NVIDIA GeForce GTX 650 Ti (8,053, 0.3%), and the NVIDIA GeForce GTX 880M (8,040, 0.5%). This puts it in a solid mid-range desktop performance tier.

The HD 8850M’s nearest rivals are a mix of integrated and low-end discrete GPUs: the Intel UHD Graphics 750 (7,441, 0.1% delta), the AMD Radeon R7 350 (7,425, 0.3%), the NVIDIA GeForce GTX 1650 (7,472, -0.3%), and the Intel Arc A310 (7,550, -1.4%). The inclusion of the GTX 1650 in that list is notable, as it suggests the HD 8850M is roughly on par with a much newer mainstream card in OpenCL, despite being a 2013 mobile chip.

For a user choosing between these two, the decision is not about performance parity, it is about form factor and use case. The GRID K2 is a server accelerator with no display outputs, designed for datacenter or workstation compute tasks. The HD 8850M is a mobile GPU for laptops, where power consumption and physical size are primary constraints. If the workload is mobile gaming or general laptop use, the HD 8850M is the only choice, as the GRID K2 cannot be installed in a laptop. If the workload is high-throughput compute in a server chassis, the GRID K2 is the clear winner, offering 42.4% more OpenCL performance.

FAQ

Q: Which GPU has higher raw compute performance in OpenCL?

A: The NVIDIA GRID K2 scores 10,602 points in Geekbench OpenCL, which is 42.4% higher than the AMD Radeon HD 8850M’s 7,447 points.

Q: What are the memory bandwidth differences between the two?

A: The GRID K2 has 160.0 GB/s of bandwidth from its 4 GB GDDR5 memory on a 256-bit bus. The HD 8850M has 64.00 GB/s from its 2 GB GDDR5 on a 128-bit bus, a 2.5x gap.

Q: Do both GPUs support the same API levels?

A: Both support OpenGL 4.6 and Vulkan (1.2.175 for the GRID K2, 1.2.170 for the HD 8850M). The HD 8850M supports DirectX 12 (11_1), while the GRID K2 supports DirectX 12 (11_0).

Q: Can the NVIDIA GRID K2 be used in a standard desktop with a monitor?

A: No, the GRID K2 has no display outputs, making it unsuitable for direct display connection. The HD 8850M is a mobile chip typically integrated into laptops with display support.

Q: How do the two compare on transistor density?

A: They are nearly identical. The GRID K2 has 12.0M / mm², while the HD 8850M has 12.2M / mm², despite the GRID K2 having a much larger die (294 mm² vs 123 mm²).

Q: What is the percentile ranking of each GPU?

A: The GRID K2 is in the 42nd percentile of all GPUs, while the HD 8850M is in the 40th percentile, based on their average benchmark scores of 8,080 and 7,447, respectively.

Head-to-Head Benchmarks

There is only one head-to-head benchmark result in the data, but it is decisive. In the Geekbench OpenCL test, the NVIDIA GRID K2 scores 10,602 points, while the AMD Radeon HD 8850M scores 7,447 points. The NVIDIA part wins by a delta of 42.4%, which is a commanding lead.

This result is consistent with the theoretical specifications. The GRID K2 has 2.4x more shading units (1,536 vs 640), 3.2x more TMUs (128 vs 40), and 2x more ROPs (32 vs 16). Its FP32 throughput of 2.289 TFLOPS is 2.86x higher than the HD 8850M’s 800.0 GFLOPS. The texture rate differential is even larger: 95.36 GTexel/s versus 25.00 GTexel/s, a 3.8x gap.

The memory subsystem amplifies this advantage. The GRID K2’s 160.0 GB/s bandwidth is 2.5x the HD 8850M’s 64.00 GB/s. With 4 GB of VRAM versus 2 GB, the GRID K2 can also hold larger datasets locally, reducing the need for host memory transfers.

The HD 8850M’s only advantages are its smaller physical footprint, lower power requirements (no TDP listed, versus the GRID K2’s 225 W), and its mobile form factor. In a head-to-head compute benchmark, those factors do not matter, and the GRID K2 wins decisively.

Looking at the nearest rivals for context, the GRID K2’s average score of 8,080 makes it competitive with the NVIDIA GeForce GTX 650 Ti Boost (8,067, within 0.2%) and the GeForce GTX 650 Ti (8,053, within 0.3%). It is slightly behind the GeForce 945M (8,099, -0.2%) and ahead of the GeForce GTX 880M (8,040, 0.5%). The HD 8850M’s 7,447 average score places it just ahead of the Intel UHD Graphics 750 (7,441, 0.1%) and the AMD Radeon R7 350 (7,425, 0.3%), but behind the NVIDIA GeForce GTX 1650 (7,472, -0.3%) and the Intel Arc A310 (7,550, -1.4%).

In summary, the GRID K2 wins the compute benchmark by a wide margin, and its architectural advantages in core count, memory bandwidth, and fill rates fully explain that result. The HD 8850M remains a viable mobile solution, but it cannot match the GRID K2 in raw performance.