AMD Radeon Pro 555X vs NVIDIA GeForce GTX 780M Comparison

The AMD Radeon Pro 555X and the NVIDIA GeForce GTX 780M represent two very different answers to the mobile workstation GPU problem: a modern 14 nm Polaris part against a much older 28 nm Kepler flagship. Both are now end-of-life, both carry 4 GB of GDDR5, and both sit near the middle of the database's historical ranking. Yet the recorded data shows they get there by completely different routes, and the head-to-head results split in a way that reveals exactly what each architecture was built for. On aggregate the Radeon Pro 555X leads with an average benchmark score of 13,321 versus 11,261 for the GTX 780M, a gap of roughly 18 percent, and it wins two of the three recorded head-to-head tests.

Head-to-Head Benchmarks

The starkest result in the dataset is Geekbench Metal, where the Radeon Pro 555X scores 14,479 against 8,319 for the GTX 780M. That is a 74 percent victory for AMD, and it is the single most decisive number in this comparison. Metal is Apple's API and the 555X's Polaris 21 silicon was designed with modern low-overhead API support in mind, so this result aligns with what the underlying architecture would predict: GCN 4.0 exposes DirectX 12 at feature level 12_0 and Vulkan 1.3, while the Kepler-based GTX 780M tops out at DirectX 12 feature level 11_0 and Vulkan 1.2.175. The older chip is simply less able to exploit a modern driver path.

The other two tests tell a different story. In Geekbench OpenCL the GTX 780M wins with 12,769 against 12,628 for the 555X, a 1.1 percent edge that is effectively a tie given normal run-to-run variance. Geekbench Vulkan flips back to AMD, 12,855 against 12,696, a 1.3 percent margin that is similarly marginal. So the honest reading of the compute data is this: in cross-platform, API-agnostic compute the two GPUs are equals, and the aggregate difference is driven almost entirely by the Metal result. When a modern explicit API with strong driver support is available, the 555X pulls far ahead; when it is not, five years of silicon advantage largely evaporates.

Context from the database reinforces how closely matched these two are in general compute. The 555X sits at the 54th percentile versus all GPUs with an average score of 13,321, and its nearest rivals cluster almost exactly around it: the GeForce GTX 480 at 13,300 (0.2 percent), the FirePro M6100 at 13,354 (-0.2 percent), the Radeon RX 5500M at 13,356 (-0.3 percent), and the Radeon HD 8950M at 13,376 (-0.4 percent). The GTX 780M sits at the 50th percentile with an average score of 11,261, bracketed by the Radeon Pro WX 3200 (11,228) and FirePro W4300 (11,225), each within 0.3 percent. Both cards are textbook mid-pack performers; neither is an outlier in either direction.

Where Each One Wins

For the Radeon Pro 555X, the case rests on modern API software and Metal specifically. Any workflow running through Metal on macOS shows the 74 percent gulf recorded in the database, which makes the 555X the clear pick for Apple-platform compute and any application built on that API. Its Vulkan 1.3 support versus 1.2.175 on the NVIDIA part also gives it the edge for software targeting newer Vulkan feature sets. The Vulkan benchmark itself agrees, if narrowly.

The GTX 780M's win is narrower but real: OpenCL, by 1.1 percent. OpenCL was the dominant cross-platform compute API of the Kepler era and remains a common fallback, so workloads stuck on OpenCL see the two cards as effectively equivalent, with the 780M fractionally ahead in the recorded run. Where the 780M holds genuine structural advantages is in raw rasterization and bandwidth hardware rather than recorded benchmark scores. The database shows 25.50 GPixel/s of pixel fill and 102.0 GTexel/s of texture fill, against 14.51 GPixel/s and 43.54 GTexel/s for the 555X, alongside 160.0 GB/s of memory bandwidth versus 94.08 GB/s. Workloads that are fill-rate-bound or bandwidth-hungry at high resolutions favor the older, larger, power-hungrier chip on paper.

The counterweight is power: the 555X is rated at 75 W against 122 W for the 780M. Per watt, the 555X is dramatically more efficient in compute throughput, and that efficiency gap is the direct consequence of the process node difference.

Architecture Differences

The two GPUs come from different technological eras. The Radeon Pro 555X uses the Polaris 21 chip on the GCN 4.0 architecture, fabricated at GlobalFoundries on a 14 nm process. It packs 3,000 million transistors into a 123 mm² die, yielding a density of 24.4M transistors per mm². The GTX 780M uses the GK104 chip on the Kepler architecture, built by TSMC on a 28 nm process, with 3,540 million transistors spread across a 294 mm² die at just 12.0M per mm². The density figure is the headline: the 555X achieves roughly double the transistor density, which is how it delivers competitive compute performance at a 75 W TDP from a die less than half the area of the GK104.

The design philosophies diverge accordingly. NVIDIA went wide: 1,536 shading units, 128 TMUs, and 32 ROPs, giving high theoretical fill rates but requiring the larger die and the 122 W envelope. AMD went efficient and modern: 768 shading units, 48 TMUs, and 16 ROPs, backed by architecture-level improvements that translate the smaller hardware into equal or better real-world compute results. The FP32 numbers illustrate the gap between theory and recorded practice: the GTX 780M's 2.448 TFLOPS peak dwarfs the 555X's 1,393.2 GFLOPS, yet the 555X wins two of three benchmarks and leads the aggregate by about 18 percent. Peak throughput on old silicon is not the same as delivered throughput through modern APIs. The 555X also supports FP16 at a 1:1 rate of 1,393.2 GFLOPS; no FP16 figure is recorded for the Kepler part.

API support marks another divide. The 555X offers DirectX 12 at feature level 12_0, OpenGL 4.6, and Vulkan 1.3. The GTX 780M offers DirectX 12 at feature level 11_0, OpenGL 4.6, and Vulkan 1.2.175. Neither card has RT cores or tensor cores; neither belongs to the ray-tracing era.

Specification Differences

The recorded fields where these two differ:

• Chip and architecture: Polaris 21 on GCN 4.0 (AMD) versus GK104 on Kepler (NVIDIA).
• Release date: 2018-07-15 for the Radeon Pro 555X versus 2013-05-10 for the GTX 780M.
• Process node and foundry: 14 nm at GlobalFoundries versus 28 nm at TSMC.
• Transistors, die size, density: 3,000 million, 123 mm², 24.4M/mm² versus 3,540 million, 294 mm², 12.0M/mm².
• Shading hardware: 768 shading units, 48 TMUs, 16 ROPs versus 1,536 shading units, 128 TMUs, 32 ROPs.
• Clocks: the GTX 780M lists a 771 MHz base and 797 MHz boost; no base or boost figures are recorded for the 555X. Memory clocks are 1470 MHz (5.9 Gbps effective) for AMD versus 1250 MHz (5 Gbps effective) for NVIDIA.
• Memory subsystem: both are 4 GB GDDR5, but the 780M uses a 256-bit bus for 160.0 GB/s against the 555X's 128-bit bus and 94.08 GB/s.
• Fill rates and compute: 14.51 GPixel/s, 43.54 GTexel/s, 1,393.2 GFLOPS FP32 for the 555X versus 25.50 GPixel/s, 102.0 GTexel/s, 2.448 TFLOPS FP32 for the 780M; the 555X additionally records 1,393.2 GFLOPS FP16 at a 1:1 rate.
• TDP: 75 W versus 122 W.
• Form factor and bus: the 555X is an IGP on PCIe 3.0 x8; the 780M is an MXM Module on MXM-B (3.0).
• API support: Vulkan 1.3 and DirectX 12_0 versus Vulkan 1.2.175 and DirectX 11_0 feature level under a 12 banner; both support OpenGL 4.6.
• Lineage: the 780M's predecessor is the GeForce 600M and its successor the GeForce 800M; no predecessor or successor is recorded for the 555X.

Memory size and type, power connectors (none for either), display outputs (portable device dependent for both), production status (both end-of-life), and launch MSRP (not recorded for either) are identical or absent across the pair.

FAQ

Q: Which GPU is faster overall according to the database?

A: The Radeon Pro 555X, with an average benchmark score of 13,321 versus 11,261 for the GTX 780M, an advantage of roughly 18 percent, and two head-to-head wins out of three tests.

Q: Why does the 555X win Metal by so much?

A: Geekbench Metal shows 14,479 for the 555X against 8,319 for the GTX 780M, a 74 percent gap. The 555X's GCN 4.0 architecture and Polaris-era driver stack support modern explicit APIs fully, while Kepler's older API support (DirectX 12 at feature level 11_0, Vulkan 1.2.175) limits it on the same path.

Q: Does the GTX 780M win anything?

A: Yes. It takes Geekbench OpenCL with 12,769 against 12,628, a 1.1 percent margin, and it holds large paper advantages in fill rate (25.50 versus 14.51 GPixel/s; 102.0 versus 43.54 GTexel/s) and memory bandwidth (160.0 versus 94.08 GB/s).

Q: How do their theoretical compute figures compare with real results?

A: The GTX 780M peaks at 2.448 TFLOPS FP32 against 1,393.2 GFLOPS for the 555X, yet the 555X wins the aggregate by about 18 percent, showing that architecture age and API support matter more than raw peak throughput in the recorded benchmarks.

Q: Which is more power-efficient?

A: The 555X. It delivers its performance at a 75 W TDP versus 122 W for the GTX 780M, enabled by a 14 nm process with 24.4M transistors per mm² against Kepler's 28 nm process at 12.0M per mm².

Q: How does each rank against all GPUs in the database?

A: The 555X sits at the 54th percentile, effectively tied with cards like the GeForce GTX 480 and FirePro M6100. The GTX 780M sits at the 50th percentile, within 0.3 percent of the Radeon Pro WX 3200 and FirePro W4300. Both are solidly mid-pack historical performers.