Intel Iris Pro Graphics P6300 vs NVIDIA GeForce GT 555M Comparison

The Verdict

The benchmark database places these two mobile graphics solutions in adjacent performance tiers, but with distinct positioning. The NVIDIA GeForce GT 555M records an average Geekbench OpenCL score of 6493, placing it in the 37th percentile of all GPUs. The Intel Iris Pro Graphics P6300 scores 5712, landing in the 33rd percentile. The head-to-head measurement shows the GT 555M winning the single recorded test by 13.7%, a substantial margin in compute workloads.

For users prioritizing raw compute performance in legacy mobile platforms, the GT 555M is the clear choice. Its score sits within 0.9% of the Intel UHD Graphics P750 (6554) and 0.3% of the AMD Radeon Vega 10 Mobile (6476), indicating it competes with much newer integrated solutions. Conversely, the Iris Pro P6300 trails the GT 555M by 13.7% in the direct comparison and sits within 1.9% of the NVIDIA Quadro M500M (5604) as its closest rival above, showing it clusters with lower-tier discrete parts.

The GT 555M is a discrete GPU with dedicated memory, while the Iris Pro P6300 is an integrated processor graphics solution. The data suggests that for compute tasks, the older discrete part holds a measurable advantage. However, the Iris Pro P6300 draws significantly less power (15 W versus 35 W), making it the sensible option for systems where thermal and power constraints dominate. The verdict from the measurements: choose the GT 555M for maximum OpenCL throughput on a legacy platform; choose the Iris Pro P6300 for a lower-power integrated solution with respectable, though lower, compute scores.

Architecture Differences

The two GPUs come from fundamentally different design philosophies. The NVIDIA GeForce GT 555M uses the GF106 chip based on the Fermi architecture, manufactured on a 40 nm process at TSMC. It integrates 1,170 million transistors on a 238 mm² die, yielding a transistor density of 4.9 million transistors per square millimeter. The Intel Iris Pro P6300 uses the Broadwell GT3e chip based on Generation 8.0 architecture, built on Intel's 14 nm process. The database does not list transistor count or die size for the Intel part.

The memory subsystems differ completely. The GT 555M has 1024 MB of dedicated DDR3 memory on a 128-bit bus, delivering 28.80 GB/s of bandwidth. The Iris Pro P6300 uses System Shared memory, with its bandwidth marked as System Dependent. This means the Intel part relies on the host system's memory controller and RAM configuration, while the NVIDIA part has its own dedicated frame buffer.

The core configurations diverge significantly. The GT 555M has 144 shading units, 24 texture mapping units, and 16 raster output units. The Iris Pro P6300 has 384 shading units, 48 TMUs, but only 6 ROPs. This configuration gives the Intel part a higher theoretical texture rate of 38.40 GTexel/s versus 14.16 GTexel/s for the NVIDIA part, and a higher pixel rate of 4.800 GPixel/s versus 3.540 GPixel/s. The Intel part also leads in FP32 compute with 614.4 GFLOPS against 339.8 GFLOPS for the GT 555M.

Clock behavior differs as well. The Iris Pro P6300 has a base clock of 300 MHz and a boost clock of 800 MHz. The GT 555M lists no base or boost clock in the database, only a memory clock of 900 MHz (1800 Mbps effective). The NVIDIA part uses a PCIe 2.0 x16 bus interface, while the Intel part uses a Ring Bus connection typical of integrated graphics.

API support shows a mixed picture. The GT 555M supports DirectX 12 (11_0) and OpenGL 4.6, with no Vulkan listed. The Iris Pro P6300 supports DirectX 12 (11_1), OpenGL 4.4, and Vulkan 1.0. The Intel part has a slightly higher DirectX feature level and adds Vulkan support, while the NVIDIA part has a newer OpenGL version.

FAQ

Q: Which GPU has the higher benchmark score?

A: The NVIDIA GeForce GT 555M scores 6493 in Geekbench OpenCL, while the Intel Iris Pro P6300 scores 5712. The GT 555M wins the head-to-head test by 13.7%.

Q: How do these GPUs compare to their nearest rivals?

A: The GT 555M is 0.2% behind the NVIDIA Quadro M5000M (6481) and 0.3% behind the AMD Radeon Vega 10 Mobile (6476), while being 0.3% ahead of the NVIDIA GeForce GTX 670M (6513) and 0.9% ahead of the Intel UHD Graphics P750 (6554). The Iris Pro P6300 is 0.1% behind the NVIDIA GeForce GTX 670MX (5721), 0.3% behind the NVIDIA GeForce GTX 550 Ti (5731), 0.4% ahead of the AMD Radeon HD 8790M (5691), and 1.9% ahead of the NVIDIA Quadro M500M (5604).

Q: What are the power consumption figures?

A: The NVIDIA GeForce GT 555M has a TDP of 35 W. The Intel Iris Pro P6300 has a TDP of 15 W, which is 20 W lower.

Q: What memory configurations do these GPUs use?

A: The GT 555M has 1024 MB of dedicated DDR3 memory on a 128-bit bus with 28.80 GB/s bandwidth. The Iris Pro P6300 uses System Shared memory with System Dependent bandwidth.

Q: Which GPU supports Vulkan?

A: The Intel Iris Pro P6300 supports Vulkan 1.0. The NVIDIA GeForce GT 555M does not list Vulkan support in the database, though it supports DirectX 12 (11_0) and OpenGL 4.6.

Q: When were these products released?

A: The NVIDIA GeForce GT 555M was released on July 1, 2011. The Intel Iris Pro P6300 was released on September 4, 2014.

Specification Differences

The database records the following differences between the two GPUs:

• Process Node: GT 555M uses 40 nm; Iris Pro P6300 uses 14 nm.
• Foundry: GT 555M uses TSMC; Iris Pro P6300 uses Intel.
• Transistors: GT 555M has 1,170 million; Iris Pro P6300 has no listed value.
• Die Size: GT 555M is 238 mm²; Iris Pro P6300 has no listed value.
• Shading Units: GT 555M has 144; Iris Pro P6300 has 384.
• TMUs: GT 555M has 24; Iris Pro P6300 has 48.
• ROPs: GT 555M has 16; Iris Pro P6300 has 6.
• Pixel Rate: GT 555M is 3.540 GPixel/s; Iris Pro P6300 is 4.800 GPixel/s.
• Texture Rate: GT 555M is 14.16 GTexel/s; Iris Pro P6300 is 38.40 GTexel/s.
• FP32: GT 555M is 339.8 GFLOPS; Iris Pro P6300 is 614.4 GFLOPS.
• TDP: GT 555M is 35 W; Iris Pro P6300 is 15 W.
• Slot Width: GT 555M has no listed value; Iris Pro P6300 is listed as IGP.
• Bus Interface: GT 555M uses PCIe 2.0 x16; Iris Pro P6300 uses Ring Bus.
• Memory Size/Type/Bus: GT 555M has 1024 MB DDR3 on 128-bit; Iris Pro P6300 uses System Shared.
• Memory Clock: GT 555M is 900 MHz (1800 Mbps effective); Iris Pro P6300 has no listed memory clock.
• Memory Bandwidth: GT 555M is 28.80 GB/s; Iris Pro P6300 is System Dependent.
• Base/Boost Clock: GT 555M has none listed; Iris Pro P6300 has 300 MHz base and 800 MHz boost.
• DirectX: GT 555M supports 12 (11_0); Iris Pro P6300 supports 12 (11_1).
• OpenGL: GT 555M supports 4.6; Iris Pro P6300 supports 4.4.
• Vulkan: GT 555M has none listed; Iris Pro P6300 supports 1.0.
• Display Outputs: GT 555M is Portable Device Dependent; Iris Pro P6300 is Motherboard Dependent.
• Release Date: GT 555M is 2011-07-01; Iris Pro P6300 is 2014-09-04.

Head-to-Head Benchmarks

The database records a single head-to-head test between these two GPUs: Geekbench OpenCL. The NVIDIA GeForce GT 555M scores 6493, while the Intel Iris Pro P6300 scores 5712. The delta is 13.7% in favor of the NVIDIA part.

This result is notable because the GT 555M wins despite having fewer shading units (144 versus 384) and lower theoretical FP32 throughput (339.8 GFLOPS versus 614.4 GFLOPS). The GT 555M's dedicated memory subsystem likely contributes to this outcome, as the Iris Pro P6300 depends on shared system memory with bandwidth that varies by platform configuration.

The GT 555M's score of 6493 places it at the 37th percentile of all GPUs. Its nearest rival above is the NVIDIA Quadro M5000M at 6481 (0.2% behind), and its nearest rival below is the NVIDIA GeForce GTX 670M at 6513 (0.3% ahead). This tight clustering indicates the GT 555M sits at a performance plateau where many discrete mobile parts from different generations converge.

The Iris Pro P6300's score of 5712 places it at the 33rd percentile. Its nearest rival above is the NVIDIA GeForce GTX 670MX at 5721 (0.1% ahead), and its nearest rival below is the AMD Radeon HD 8790M at 5691 (0.4% behind). The 1.9% gap to the NVIDIA Quadro M500M at 5604 shows the Intel part has a measurable advantage over that lower-tier discrete GPU.

The single benchmark result shows a decisive win for the NVIDIA part, with a 13.7% margin that places the two GPUs in clearly different performance brackets. The GT 555M clusters with mid-range discrete GPUs from the 2012-2015 era, while the Iris Pro P6300 clusters with lower-tier discrete parts. Despite the Intel part's architectural advantages in raw throughput metrics, the real-world compute benchmark favors the older Fermi-based discrete GPU with its dedicated memory interface.