AMD Radeon HD 8850M vs AMD Radeon Vega 8 Mobile Comparison

The AMD Radeon HD 8850M and the AMD Radeon Vega 8 Mobile represent two very different generations of mobile graphics, separated by nearly six years of architectural evolution. The data reveals a surprisingly close contest in raw compute benchmarks, yet the underlying specifications tell a story of divergent design philosophies. The HD 8850M, a discrete part from 2013, edges out the newer integrated Vega 8 Mobile in a single OpenCL test, but the Vega part counters with modern API support and a significantly higher transistor density, suggesting that the final verdict depends heavily on the specific workload and system context.

Head-to-Head Benchmarks

The only direct benchmark comparison available is the Geekbench OpenCL test, and it is exceptionally tight. The AMD Radeon HD 8850M scores 7,447, while the AMD Radeon Vega 8 Mobile scores 7,435. This gives the HD 8850M a win with a delta of just 0.2 percent. For practical purposes, this is a statistical tie, placing both GPUs within a hair’s breadth of each other in raw compute throughput. The HD 8850M’s victory is so narrow that it falls within the margin of error for most benchmarking tools, meaning that day-to-day performance in OpenCL-accelerated applications would be indistinguishable between the two.

This near-identical score is remarkable given the architectural chasm between them. The HD 8850M achieves its result with a 28 nm process, 640 shading units, and a boost clock of 625 MHz. The Vega 8 Mobile, in contrast, uses a 14 nm process, 512 shading units, and a much higher boost clock of 1,101 MHz. The data implies that the Vega 8 Mobile’s higher clock speed and newer instruction set are almost exactly offset by the HD 8850M’s larger number of shading units and dedicated GDDR5 memory. The margin is so small that the 0.2 percent delta separates them, but the performance envelope is essentially identical. When compared to their respective rivals, both parts sit in a similar performance tier. The HD 8850M is 0.1 percent ahead of the Intel UHD Graphics 750 and 0.3 percent ahead of the AMD Radeon R7 350, while the Vega 8 Mobile is 0.3 percent behind the NVIDIA GeForce GTX 750 and 0.4 percent ahead of the NVIDIA GeForce GTX 560 SE.

Where Each One Wins

The benchmark data shows a single win for the HD 8850M, but the specification sheet reveals where each GPU is designed to excel. The HD 8850M wins in the OpenCL compute test, and its dedicated memory subsystem is a clear advantage. With 2 GB of GDDR5 memory on a 128-bit bus, it offers 64.00 GB/s of bandwidth. This is a fixed, dedicated pool of fast memory that does not compete with the CPU for system resources. For workloads that are bandwidth-sensitive, such as texture-heavy rendering or certain compute tasks, this dedicated allocation is likely the reason for its marginal OpenCL victory. The HD 8850M’s pixel rate of 10.00 GPixel/s is also higher than the Vega 8 Mobile’s 8.808 GPixel/s, suggesting it can handle fill-rate-limited scenarios slightly better.

The Vega 8 Mobile, despite losing the benchmark, wins in several qualitative and forward-looking categories. Its integrated nature means it uses System Shared memory, with bandwidth that is System Dependent. This is a disadvantage in raw terms, but it also means the GPU can access a potentially large pool of system RAM, limited only by the laptop’s total memory. The Vega 8 Mobile also has a superior texture rate of 35.23 GTexel/s compared to the HD 8850M’s 25.00 GTexel/s. This is a significant 40 percent advantage in texture fill rate, which can be decisive in games and applications that rely heavily on textured geometry. Furthermore, the Vega 8 Mobile’s support for DirectX 12 (12_1) and Vulkan 1.3 gives it a clear edge in modern titles that leverage these APIs, whereas the HD 8850M is limited to DirectX 12 (11_1) and Vulkan 1.2.170.

Architecture Differences

The architectural divide is stark. The HD 8850M is built on GCN 1.0, a first-generation Graphics Core Next design, fabricated on a 28 nm process at TSMC. Its chip, codenamed Venus, contains 1,500 million transistors on a die size of 123 mm², resulting in a transistor density of 12.2 million per square millimeter. The Vega 8 Mobile, in contrast, uses GCN 5.0, the fifth-generation iteration, fabricated on a 14 nm process at GlobalFoundries. Its Raven-M chip is substantially larger, with 4,940 million transistors on a 210 mm² die, achieving a much higher density of 23.5 million per square millimeter. This more than doubling of transistor density reflects the significant advancements in design and manufacturing efficiency over the six years between their releases.

The compute resources differ in configuration. The HD 8850M has 640 shading units, 40 texture mapping units (TMUs), and 16 render output units (ROPs). The Vega 8 Mobile has fewer shading units at 512, fewer TMUs at 32, and critically, only half the ROPs at 8. This explains the HD 8850M’s higher pixel rate. However, the Vega 8 Mobile’s boost clock of 1,101 MHz is dramatically higher than the HD 8850M’s 625 MHz, which helps it close the gap in raw throughput. The Vega 8 Mobile also supports FP16 computation at 2.255 TFLOPS with a 2:1 ratio, while the HD 8850M has no listed FP16 capability. This makes the Vega part significantly more capable in workloads that can utilize half-precision math, such as certain AI inference tasks or image processing filters. The memory interface is another fundamental difference: the HD 8850M uses a dedicated 128-bit GDDR5 bus, while the Vega 8 Mobile relies entirely on the system’s shared memory, making its performance dependent on the laptop’s RAM configuration.

FAQ

Q: Which GPU has a higher raw compute score in OpenCL?

A: The AMD Radeon HD 8850M scores 7,447 in Geekbench OpenCL, which is 0.2 percent higher than the AMD Radeon Vega 8 Mobile’s score of 7,435.

Q: Does the Vega 8 Mobile support more modern graphics APIs?

A: Yes. The Vega 8 Mobile supports DirectX 12 (12_1) and Vulkan 1.3, while the HD 8850M is limited to DirectX 12 (11_1) and Vulkan 1.2.170.

Q: What is the difference in memory bandwidth?

A: The HD 8850M has a fixed 64.00 GB/s of bandwidth from its 2 GB GDDR5 memory on a 128-bit bus, whereas the Vega 8 Mobile uses System Shared memory, making its bandwidth System Dependent.

Q: Which GPU has a higher texture fill rate?

A: The Vega 8 Mobile has a texture rate of 35.23 GTexel/s, which is significantly higher than the HD 8850M’s 25.00 GTexel/s.

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

A: The HD 8850M has an average score of 7,447, placing it 0.1 percent ahead of the Intel UHD Graphics 750 and 0.3 percent ahead of the AMD Radeon R7 350. The Vega 8 Mobile has an average score of 7,203, which is 0.3 percent behind the NVIDIA GeForce GTX 750 and 0.4 percent ahead of the NVIDIA GeForce GTX 560 SE.

Q: What are the transistor counts and process nodes for each?

A: The HD 8850M is built on a 28 nm process with 1,500 million transistors, while the Vega 8 Mobile uses a 14 nm process with 4,940 million transistors.

Specification Differences

The two GPUs differ in nearly every major specification category, reflecting their distinct positions in the market.

• Process Node: The HD 8850M uses a 28 nm process from TSMC, while the Vega 8 Mobile uses a 14 nm process from GlobalFoundries.
• Transistors: The HD 8850M has 1,500 million transistors, compared to 4,940 million in the Vega 8 Mobile.
• Die Size: The HD 8850M’s die is 123 mm², while the Vega 8 Mobile’s is 210 mm².
• Transistor Density: The HD 8850M has a density of 12.2M / mm², whereas the Vega 8 Mobile achieves 23.5M / mm².
• Base Clock: The HD 8850M has a base clock of 575 MHz, while the Vega 8 Mobile’s base clock is 300 MHz.
• Boost Clock: The HD 8850M boosts to 625 MHz; the Vega 8 Mobile boosts to 1,101 MHz.
• Memory: The HD 8850M uses 2 GB of GDDR5 with a 128-bit bus and 64.00 GB/s bandwidth. The Vega 8 Mobile uses System Shared memory with System Dependent bandwidth.
• Shading Units: The HD 8850M has 640, while the Vega 8 Mobile has 512.
• TMUs: The HD 8850M has 40, while the Vega 8 Mobile has 32.
• ROPs: The HD 8850M has 16, while the Vega 8 Mobile has only 8.
• Pixel Rate: The HD 8850M achieves 10.00 GPixel/s, versus 8.808 GPixel/s for the Vega 8 Mobile.
• Texture Rate: The HD 8850M achieves 25.00 GTexel/s, versus 35.23 GTexel/s for the Vega 8 Mobile.
• FP32 Performance: The HD 8850M delivers 800.0 GFLOPS, while the Vega 8 Mobile delivers 1,127.4 GFLOPS.
• FP16 Performance: The HD 8850M has no listed FP16 capability, while the Vega 8 Mobile offers 2.255 TFLOPS (2:1).
• TDP: The HD 8850M has no listed TDP, while the Vega 8 Mobile is rated at 25 W.
• Slot Width: The HD 8850M has no listed slot width, while the Vega 8 Mobile is an IGP.
• Power Connectors: The HD 8850M has none listed, while the Vega 8 Mobile requires None.
• Bus Interface: The HD 8850M uses PCIe 3.0 x16, while the Vega 8 Mobile uses IGP.
• Display Outputs: The HD 8850M has none listed, while the Vega 8 Mobile is Portable Device Dependent.
• DirectX Support: The HD 8850M supports 12 (11_1), while the Vega 8 Mobile supports 12 (12_1).
• Vulkan Support: The HD 8850M supports 1.2.170, while the Vega 8 Mobile supports 1.3.
• Release Date: The HD 8850M was released in 2013-03-31, while the Vega 8 Mobile was released in 2019-01-07.

The Verdict

The data presents a nuanced picture. For users who prioritize raw OpenCL compute performance, the AMD Radeon HD 8850M is the nominal winner, with its 7,447 score edging out the Vega 8 Mobile’s 7,435. Its dedicated 2 GB of GDDR5 memory with 64.00 GB/s of bandwidth provides a stable, predictable memory subsystem that does not depend on the rest of the system. The HD 8850M also has a higher pixel rate of 10.00 GPixel/s, making it a better choice for tasks that are fill-rate bound. Its percentile rank of 40 is also slightly higher than the Vega 8 Mobile’s 39, placing it marginally better relative to the entire GPU landscape.

However, the Vega 8 Mobile is the more future-proof and versatile option. Its support for DirectX 12 (12_1) and Vulkan 1.3 means it can run modern games and applications that require these APIs, while the HD 8850M’s older 11_1 and 1.2.170 support may lock it out of newer titles. The Vega 8 Mobile’s FP16 capability and 1,127.4 GFLOPS of FP32 performance are also significantly higher, making it a more capable compute part for applications that can leverage these features. Its lower TDP of 25 W and IGP form factor suggest it is designed for efficient, thin-and-light laptops, whereas the HD 8850M is a discrete part from a bygone era. The choice is clear: the HD 8850M wins a narrow benchmark victory, but the Vega 8 Mobile is the more capable, modern, and efficient GPU for a current system.