NVIDIA GeForce GT 555M vs NVIDIA Quadro K620M Comparison

Head-to-Head Benchmarks

The benchmark data shows a single decisive result between these two mobile GPUs. In the Geekbench OpenCL test, the NVIDIA GeForce GT 555M scores 6,493 points, while the NVIDIA Quadro K620M scores 5,957 points. That gives the GT 555M a 9% advantage, the only head-to-head comparison recorded in the database. This is not a narrow margin; it is a clear, measurable lead in raw compute performance.

The GT 555M's score places it at the 37th percentile among all GPUs, whereas the K620M sits at the 34th percentile. That three-point gap in percentile ranking reinforces what the raw numbers show: the older Fermi-based part outperforms the newer Maxwell-based part in this specific workload. The nearest rivals for the GT 555M include the NVIDIA Quadro M5000M, which scores 6,481 points, just 0.2% behind, and the AMD Radeon Vega 10 Mobile at 6,476 points, 0.3% behind. On the other side, the NVIDIA GeForce GTX 670M edges out the GT 555M with 6,513 points, a 0.3% delta, and the Intel UHD Graphics P750 leads by 0.9% with 6,554 points. The GT 555M occupies a tight cluster where a single benchmark run can shift rankings.

For the K620M, the competitive picture is equally tight but at a lower performance tier. Its nearest rivals include the AMD Radeon HD 8730M at 5,955 points, essentially a tie with a 0% delta, and the AMD Radeon HD 8750M at 5,970 points, which is 0.2% faster. The NVIDIA Quadro K4000 scores 5,982 points, 0.4% ahead, while the Intel UHD Graphics 730 trails by 0.5% with 5,929 points. The K620M sits in a crowded field where small score differences separate it from its peers, but none of those rivals close the 9% gap to the GT 555M.

The delta of 9% is substantial enough to be meaningful in real-world terms. In OpenCL compute tasks, a 9% difference can translate into noticeably shorter render times or faster data processing. The data does not show any test where the K620M wins; the wins tally stands at one for the GT 555M and zero for the K620M.

Where Each One Wins

The NVIDIA GeForce GT 555M wins the only benchmark category present in the database, which is Geekbench OpenCL. This makes it the stronger choice for general-purpose compute workloads that leverage OpenCL acceleration. Its 6,493 score reflects a GPU that can handle parallel processing tasks with reasonable efficiency, positioning it above several desktop and mobile parts from its era.

The NVIDIA Quadro K620M does not win any recorded benchmark category. However, the absence of a win does not mean it lacks utility. The K620M's 5,957 score still places it within striking distance of several mid-range mobile GPUs, and its 34th percentile ranking indicates it outperforms a significant portion of the GPU landscape. For users whose primary concern is OpenCL compute, the GT 555M is the clear choice. For users who prioritize other aspects of GPU performance, such as driver certifications or specific professional application support, the benchmark data alone does not capture those factors.

The use-case split is straightforward: the GT 555M is the compute-focused pick, while the K620M may appeal to those who need a different feature set, even if it sacrifices raw OpenCL throughput. The data does not support any scenario where the K620M outperforms the GT 555M in the tested workload.

FAQ

Q: Which GPU scores higher in Geekbench OpenCL?

A: The NVIDIA GeForce GT 555M scores 6,493, which is 9% higher than the NVIDIA Quadro K620M's 5,957.

Q: How does the GT 555M compare to its closest rivals?

A: The GT 555M is 0.2% ahead of the NVIDIA Quadro M5000M, 0.3% ahead of the AMD Radeon Vega 10 Mobile, 0.3% behind the NVIDIA GeForce GTX 670M, and 0.9% behind the Intel UHD Graphics P750.

Q: What is the K620M's competitive position?

A: The K620M is essentially tied with the AMD Radeon HD 8730M at a 0% delta, 0.2% behind the AMD Radeon HD 8750M, 0.4% behind the NVIDIA Quadro K4000, and 0.5% ahead of the Intel UHD Graphics 730.

Q: What are the percentile rankings for both GPUs?

A: The GT 555M ranks at the 37th percentile among all GPUs, while the K620M ranks at the 34th percentile.

Q: Does the K620M win any benchmark against the GT 555M?

A: No, the database records zero wins for the K620M in head-to-head comparisons; the GT 555M holds all wins.

Q: Which GPU has the higher average benchmark score?

A: The GT 555M has an average benchmark score of 6,493, while the K620M's average is 5,957.

Specification Differences

The two GPUs differ across nearly every core specification. The GT 555M uses a 128-bit memory bus with 1,024 MB of DDR3 memory, while the K620M uses a 64-bit bus with 2,048 MB of DDR3 memory. Memory bandwidth tells the opposite story: the GT 555M delivers 28.80 GB/s, while the K620M manages only 16.02 GB/s, a significant disadvantage for the newer part.

Clock speeds differ substantially. The GT 555M has no recorded base or boost clock, but its memory runs at 900 MHz with 1,800 Mbps effective. The K620M has a base clock of 1,029 MHz and a boost clock of 1,124 MHz, with memory at 1,001 MHz and 2 Gbps effective. The K620M's higher clocks do not compensate for its narrower memory bus.

Compute resources show a mixed picture. The GT 555M has 144 shading units, 24 texture mapping units, and 16 raster output units. The K620M has 384 shading units, 16 TMUs, and 8 ROPs. The K620M has more than double the shading units, yet it scores lower in OpenCL, indicating that raw shader count does not translate directly to compute performance in this test.

Pixel and texture rates favor the K620M in some respects. The K620M achieves 8.992 GPixel/s and 17.98 GTexel/s, while the GT 555M achieves 3.540 GPixel/s and 14.16 GTexel/s. However, floating-point performance strongly favors the K620M on paper: 863.2 GFLOPS versus 339.8 GFLOPS. The benchmark result contradicts the theoretical FP32 advantage, highlighting that the GT 555M's architecture or driver implementation delivers better real-world OpenCL performance.

Thermal design power differs modestly: the GT 555M is rated at 35 W, the K620M at 30 W. The bus interface also differs, with the GT 555M using PCIe 2.0 x16 and the K620M using MXM-A (3.0). The K620M lists its slot width as MXM Module and has no power connectors, while the GT 555M has no recorded slot width or power connector details.

Architecture Differences

The architectural divide is clear. The GT 555M uses the GF106 chip based on the Fermi architecture, manufactured on a 40 nm process at TSMC. It packs 1,170 million transistors into a 238 mm² die, giving a transistor density of 4.9 million per mm². The K620M uses the GM108S chip based on the Maxwell architecture, also built by TSMC but on a 28 nm process. It contains 1,020 million transistors in a much smaller 77 mm² die, yielding a transistor density of 13.2 million per mm², nearly three times higher.

The generation labels reflect different lineages. The GT 555M belongs to the GeForce 500M generation, with the GeForce 400M as its predecessor and the GeForce 600M as its successor. The K620M is listed under the Quadro Kepler-M (Kx200M) generation, with the Quadro Fermi-M as its predecessor and the Quadro Maxwell-M as its successor. Despite the K620M's generation name mentioning Kepler, its chip is Maxwell-based, an inconsistency in the naming that the database records as-is.

API support shows a few differences. Both support DirectX 12 (11_0) and OpenGL 4.6. The K620M additionally supports Vulkan 1.4, while the GT 555M has no recorded Vulkan support. This gives the K620M a compatibility edge for modern applications that rely on Vulkan.

Display outputs are listed as portable device dependent for both, indicating that the specific outputs vary by laptop implementation. The production status for both is end-of-life. Release dates differ by several years: the GT 555M launched in July 2011, while the K620M launched in February 2015.

The Verdict

The data points to a clear winner for OpenCL compute workloads: the NVIDIA GeForce GT 555M. Its 9% benchmark lead over the K620M, combined with a higher percentile ranking, makes it the superior choice for anyone running GPU-accelerated compute tasks. The GT 555M also offers more than double the memory bandwidth, which likely contributes to its benchmark success despite its older architecture and lower theoretical FP32 output.

The NVIDIA Quadro K620M is not without merit. It offers twice the memory capacity, higher clock speeds, more shading units, and a more modern Maxwell architecture with Vulkan support. Its lower power draw of 30 W makes it a more efficient part on paper. However, the recorded benchmark does not support any scenario where the K620M outperforms the GT 555M.

Users who need raw OpenCL performance should choose the GT 555M. Its 6,493 score and 37th percentile ranking place it above the K620M and many of its own contemporaries. Users who need Vulkan support, larger memory capacity, or a smaller die may prefer the K620M, but they must accept a 9% compute deficit. The database records one win for the GT 555M and zero for the K620M, and no other benchmark data exists to alter that conclusion.