NVIDIA GeForce 825M vs NVIDIA GeForce GT 755M Comparison

The NVIDIA GeForce GT 755M and the NVIDIA GeForce 825M are both end-of-life mobile graphics solutions from NVIDIA, but they target different segments of the market. The data in this comparison is drawn from a single shared benchmark test, the Geekbench OpenCL compute workload, alongside their respective architectural specifications. The GT 755M emerges as the clear performance leader based on the available metrics, though the 825M presents a distinct set of trade-offs in power and physical design.

Head-to-Head Benchmarks

The only direct benchmark comparison available is the Geekbench OpenCL test, which measures raw compute throughput. In this test, the NVIDIA GeForce GT 755M scores 4934, while the NVIDIA GeForce 825M scores 3694. This represents a 33.6% advantage for the GT 755M, a substantial margin that places the two cards in different performance tiers. The GT 755M’s score is not just a marginal win; it is a decisive one, indicating that the 755M is significantly more capable in compute-heavy workloads such as GPGPU acceleration and certain rendering tasks.

To contextualize the GT 755M’s performance, its average benchmark score across all tests is 4033, placing it in the 24th percentile of all GPUs. Its nearest rivals include the AMD FirePro M4150 (avg score 4013, delta 0.5%), the Intel HD Graphics 630 (avg score 4075, delta -1%), and the AMD Radeon HD 6850 X2 (avg score 3977, delta 1.4%). The GT 755M’s OpenCL score of 4934 is well above its own average, suggesting that its compute performance is a relative strength compared to its overall standing in the broader GPU landscape. The 825M, by contrast, has an average benchmark score of 3694, which is its only recorded score, and sits in the 22nd percentile. Its nearest rivals are the NVIDIA GeForce GT 740M (avg score 3717, delta -0.6%), the NVIDIA Quadro 3000M (avg score 3718, delta -0.6%), and the AMD Radeon HD 6770 (avg score 3649, delta 1.2%). The 825M’s performance is closely clustered with these rivals, indicating that it is a mid-to-low tier mobile part, whereas the GT 755M’s score pushes it closer to more capable discrete solutions.

The 33.6% delta in the head-to-head test is the single most important comparative data point. It demonstrates that for any user prioritizing raw compute performance, the GT 755M is the unequivocal choice between these two. The 825M’s lower score means it will struggle more with demanding compute tasks, though its other characteristics may be more appealing in specific scenarios, which will be explored in the following sections.

Where Each One Wins

Based on the benchmark data, the NVIDIA GeForce GT 755M wins the only direct comparison test. Its 4934 OpenCL score versus the 825M’s 3694 gives it a 33.6% lead, making it the superior option for any workload that leverages OpenCL acceleration. This includes tasks like video encoding, scientific computation, and some forms of content creation, where the higher compute throughput will translate into faster processing times. The GT 755M’s higher pixel rate (8.160 GPixel/s vs 7.528 GPixel/s) and texture rate (32.64 GTexel/s vs 30.11 GTexel/s) further support its advantage in graphics-intensive scenarios, suggesting it can push more pixels and texels per second, which is beneficial for gaming and 3D rendering.

The NVIDIA GeForce 825M, while losing the compute benchmark, has its own areas of relative strength. Its TDP is 33 W, compared to the GT 755M’s 50 W. This lower power draw is a significant advantage for thin-and-light laptops where thermal management and battery life are critical. The 825M is an IGP (Integrated Graphics Processor) form factor, whereas the GT 755M is an MXM Module. This means the 825M is designed to be soldered directly onto the motherboard, saving space and reducing complexity, which is ideal for ultraportable designs. The GT 755M, being an MXM module, is a replaceable component, offering more flexibility for upgrades but requiring more physical space and power delivery. Therefore, the 825M wins in the categories of power efficiency and physical integration, making it a better fit for systems where size and battery life are prioritized over raw performance. The data shows a clear performance winner and a clear efficiency winner.

Architecture Differences

The two GPUs share a common manufacturer and foundry, but their underlying chips and architectures differ in key ways. The GT 755M is built on the GK107 chip using the original Kepler architecture, while the 825M uses the GK208 chip with the Kepler 2.0 architecture. Both are fabricated on TSMC’s 28 nm process node, a mature node for their respective release generations. The transistor counts differ: the GT 755M has 1,270 million transistors on a 118 mm² die, resulting in a transistor density of 10.8M / mm². The 825M has 1,020 million transistors on a smaller 87 mm² die, giving it a higher transistor density of 11.7M / mm². This indicates that the 825M’s chip is more densely packed, likely due to architectural refinements in Kepler 2.0.

The most critical architectural difference lies in the memory subsystem. The GT 755M utilizes 2 GB of GDDR5 memory on a 128-bit bus, delivering a bandwidth of 86.40 GB/s. In contrast, the 825M uses 1024 MB (1 GB) of DDR3 memory on a 64-bit bus, yielding a significantly lower bandwidth of just 14.40 GB/s. This is a six-fold difference in raw memory bandwidth and is the primary reason for the GT 755M’s superior performance in memory-intensive workloads. The 825M’s memory clock is 900 MHz (1800 Mbps effective), while the GT 755M’s memory clock is 1350 MHz (5.4 Gbps effective). The GT 755M’s memory is not only faster but also wider, providing a massive advantage in data throughput.

The core configurations are identical in one respect: both have 384 shading units and 32 texture mapping units (TMUs). However, the GT 755M has 16 ROPs (Render Output Units), double the 8 ROPs found on the 825M. This means the GT 755M can process twice as many pixels per clock cycle, contributing to its higher pixel rate of 8.160 GPixel/s versus the 825M’s 7.528 GPixel/s. The clock speeds also differ, with the GT 755M running at a base of 980 MHz and a boost of 1020 MHz, while the 825M runs at a base of 850 MHz and a boost of 941 MHz. The combination of higher clocks, more ROPs, and vastly superior memory bandwidth explains the GT 755M’s 33.6% lead in the OpenCL benchmark. The FP32 performance is 783.4 GFLOPS for the GT 755M and 722.7 GFLOPS for the 825M, showing a smaller gap in raw compute units than the benchmark results might suggest, highlighting the importance of memory bandwidth.

FAQ

Q: Which GPU is faster in the Geekbench OpenCL test?

A: The NVIDIA GeForce GT 755M is faster, scoring 4934 compared to the NVIDIA GeForce 825M’s score of 3694. This represents a 33.6% performance advantage for the GT 755M.

Q: What are the key differences in memory configuration?

A: The GT 755M uses 2 GB of GDDR5 memory on a 128-bit bus with a bandwidth of 86.40 GB/s. The 825M uses 1024 MB of DDR3 memory on a 64-bit bus with a bandwidth of only 14.40 GB/s. This is the most significant architectural difference between the two.

Q: Do both GPUs have the same number of shading units?

A: Yes, both the GT 755M and the 825M feature 384 shading units and 32 TMUs. However, the GT 755M has 16 ROPs, while the 825M has only 8 ROPs.

Q: Which GPU has a lower power consumption?

A: The NVIDIA GeForce 825M has a lower TDP of 33 W, while the NVIDIA GeForce GT 755M has a TDP of 50 W. The 825M is also an IGP form factor, making it more suitable for power-constrained, thin-and-light laptops.

Q: What is the difference in their physical form factors?

A: The GT 755M is an MXM Module, which is a replaceable card. The 825M is an IGP, meaning it is integrated directly onto the motherboard. This affects serviceability and the type of laptop chassis they can be used in.

Q: How do their average benchmark scores compare to their nearest rivals?

A: The GT 755M has an average score of 4033, which is within 1.5% of rivals like the AMD Radeon RX 9060 XT 8 GB (4093). The 825M has an average score of 3694, which is within 1.2% of the AMD Radeon HD 6770 (3649) and within 0.6% of the NVIDIA GeForce GT 740M (3717).

Specification Differences

| Specification | NVIDIA GeForce GT 755M | NVIDIA GeForce 825M |

| :--- | :--- | :--- |

| Architecture | Kepler | Kepler 2.0 |

| Chip | GK107 | GK208 |

| Transistors | 1,270 million | 1,020 million |

| Die Size | 118 mm² | 87 mm² |

| Transistor Density | 10.8M / mm² | 11.7M / mm² |

| Base Clock | 980 MHz | 850 MHz |

| Boost Clock | 1020 MHz | 941 MHz |

| Memory Clock | 1350 MHz / 5.4 Gbps effective | 900 MHz / 1800 Mbps effective |

| Memory Size | 2 GB | 1024 MB |

| Memory Type | GDDR5 | DDR3 |

| Memory Bus Width | 128 bit | 64 bit |

| Memory Bandwidth | 86.40 GB/s | 14.40 GB/s |

| ROPs | 16 | 8 |

| Pixel Rate | 8.160 GPixel/s | 7.528 GPixel/s |

| Texture Rate | 32.64 GTexel/s | 30.11 GTexel/s |

| FP32 Performance | 783.4 GFLOPS | 722.7 GFLOPS |

| TDP | 50 W | 33 W |

| Slot Width | MXM Module | IGP |

| Bus Interface | PCIe 3.0 x16 | PCIe 3.0 x8 |

| Release Date | 2013-06-24 | 2014-01-26 |

| Predecessor | GeForce 600M | GeForce 700M |

| Successor | GeForce 800M | GeForce 900M |