AMD Athlon PRO 300U vs Intel Core i3-8121U Comparison

FAQ

Q: Which processor has a higher average benchmark score?

A: The Intel Core i3-8121U has an average benchmark score of 1209, while the AMD Athlon PRO 300U scores 1193, a difference of 16 points.

Q: How do the two chips compare in multi-core rendering workloads?

A: In Cinebench R23 multi-core, the Intel Core i3-8121U scores 3637 versus 3468 for the AMD Athlon PRO 300U, giving Intel a 4.9% lead in that test.

Q: Are both processors limited to the same number of cores and threads?

A: Yes, both are 2-core, 4-thread mobile parts, and both have a 15 W TDP.

Q: Which processor includes integrated graphics?

A: The AMD Athlon PRO 300U features Radeon Vega 3 integrated graphics, whereas the Intel Core i3-8121U has no integrated graphics listed in the database.

Q: What is the process node difference between the two?

A: The Intel Core i3-8121U is built on Intel's 10 nm node, while the AMD Athlon PRO 300U uses GlobalFoundries' 14 nm process.

Q: Which chip holds the single-core performance edge in Cinebench R20?

A: The Intel Core i3-8121U leads with a score of 215 versus 205 for the AMD Athlon PRO 300U, a 4.9% advantage.

Architecture Differences

The Intel Core i3-8121U is built on the Cannon Lake architecture, a 10 nm process from Intel, and is part of the Core i3 generation listed as Kaby Lake-U Refresh. Its die size is 70.52 mm², and it uses the Intel BGA 1440 socket. The AMD Athlon PRO 300U, by contrast, uses the Zen architecture with the Raven Ridge 2 codename, manufactured on GlobalFoundries' 14 nm node, and fits into the AMD Socket FP5. The process node difference is significant: 10 nm versus 14 nm, though the database does not record a die size for the AMD part.

Cache hierarchies differ notably. The Intel chip has 64 KB of L1 per core and 256 KB of L2 per core, while the AMD chip doubles both: 128 KB L1 per core and 512 KB L2 per core. Both share 4 MB of L3, but the per-core L2 advantage for AMD could benefit workloads with frequent data reuse. Memory support is DDR4 dual-channel for both, though the database lists a memory bandwidth of 38.4 GB/s only for the Intel part; no bandwidth figure is recorded for the AMD chip.

Feature differences are stark. The Intel Core i3-8121U has PCIe Gen 3 with 16 lanes (CPU only), while the AMD Athlon PRO 300U has no PCIe data recorded. Integrated graphics are present only on the AMD side: Radeon Vega 3. The Intel part lacks integrated graphics entirely in the database. Production status also differs: Intel is end-of-life, while AMD is active. The release dates show Intel launched on 2018-05-04, and AMD came later on 2019-04-07. Both are mobile-segment parts with locked multipliers.

Head-to-Head Benchmarks

The head-to-head results are consistent across all recorded tests: the Intel Core i3-8121U wins every single benchmark, but by a uniform margin. In Cinebench R15 multi-core, Intel scores 366 versus AMD's 349, a 4.9% delta. That same 4.9% repeats exactly in Cinebench R20 multi-core, where Intel posts 1527 against 1456, and in Cinebench R20 single-core, 215 versus 205.

The pattern holds for the more recent Cinebench R23 tests. Multi-core sees Intel at 3637 and AMD at 3468, again a 4.9% gap. Single-core in R23 shows 513 for Intel and 489 for AMD, with the same delta. The database records five head-to-head benchmarks, and Intel wins all five, with a 5-0 win tally. No AMD win appears in any recorded test.

Interpreting these numbers: the 4.9% advantage is modest but real, and it appears consistently across both single-core and multi-core workloads. The Intel chip does not just edge ahead in one test, it holds the same relative lead in every rendering benchmark. That uniformity suggests a clock or IPC advantage that scales across thread counts. The AMD part is not far behind, but it never overtakes.

Specification Differences

The two processors differ in several core specifications, though they share the same core count, thread count, and TDP. The base clock for the AMD Athlon PRO 300U is 2.40 GHz versus 2.20 GHz for the Intel Core i3-8121U, and the boost clock is 3.30 GHz versus 3.20 GHz. Despite the higher clocks, AMD loses every benchmark, indicating that Intel's architecture delivers more performance per clock in these tests.

Socket and packaging are entirely different: Intel uses BGA 1440, AMD uses FP5. The process node is 10 nm for Intel and 14 nm for AMD, with Intel's foundry being Intel itself and AMD's being GlobalFoundries. The AMD chip has double the L1 and L2 cache per core, but both have the same 4 MB shared L3. Memory bandwidth is recorded only for Intel at 38.4 GB/s, though both support DDR4 and dual-channel configurations. ECC support is absent on both.

Integrated graphics is a major differentiator: AMD includes Radeon Vega 3, while Intel has none listed. PCIe support is only documented for Intel (Gen 3, 16 lanes, CPU only). The Intel part has a part number (SRCVC), while AMD's is not listed. Production status also differs, with Intel marked end-of-life and AMD active. Release dates are separated by about 11 months.

Where Each One Wins

Intel Core i3-8121U wins in: Every recorded CPU benchmark. It leads in Cinebench R15 multi-core (366 vs 349), Cinebench R20 multi-core (1527 vs 1456), Cinebench R20 single-core (215 vs 205), Cinebench R23 multi-core (3637 vs 3468), and Cinebench R23 single-core (513 vs 489). The 4.9% margin is identical across all tests, so Intel wins regardless of workload type, whether single-threaded or fully loaded. Its 10 nm process and higher IPC appear to offset AMD's clock advantage. The Intel chip also has a higher average benchmark score (1209 vs 1193) and a slightly better percentile ranking (34th vs 33rd percentile among all CPUs).

AMD Athlon PRO 300U wins in: Integrated graphics. The Radeon Vega 3 is the only feature where AMD has a clear functional advantage, as the Intel part has no iGPU at all. For systems that need a display output without a discrete graphics card, the AMD chip is the only option between the two. AMD also holds higher base and boost clocks (2.40 and 3.30 GHz vs 2.20 and 3.20 GHz), which could translate to better responsiveness in lightly threaded scenarios, though the benchmark data does not show an actual performance win. The AMD chip remains in active production, so it may be easier to source for new designs.

The Verdict

The data is unambiguous: the Intel Core i3-8121U is the faster processor in every CPU benchmark recorded. Its 4.9% lead in Cinebench R15, R20, and R23, across both single-core and multi-core, shows a consistent architecture advantage, despite AMD having higher clock speeds. The Intel chip also posts a higher average benchmark score (1209 vs 1193) and a higher percentile ranking (34th vs 33rd). For pure computational performance, Intel is the pick.

However, the AMD Athlon PRO 300U is not without merit. It includes Radeon Vega 3 integrated graphics, which the Intel part lacks entirely. That makes AMD the only choice when a discrete GPU is not available and a display output is required. AMD also has higher base and boost clocks, and it remains in active production, while Intel is end-of-life.

The decision comes down to system requirements. If the workload is CPU-heavy rendering, the Intel Core i3-8121U wins every test by the same 4.9% margin, and its 10 nm process suggests better power efficiency per unit of work, though the TDP is identical at 15 W. If the system needs integrated graphics or a currently produced part, the AMD Athlon PRO 300U is the functional option. The benchmark record shows no scenario where AMD wins a CPU test, so for compute-only tasks, Intel is the verdict. For all-in-one mobile designs needing graphics, AMD is the only viable path.