AMD Ryzen 3 5400U vs Intel Core i5-8600K Comparison

Head-to-Head Benchmarks

The benchmark data presents a fascinating split between these two processors. AMD Ryzen 3 5400U dominates the Cinebench suite, while Intel Core i5-8600K takes the Geekbench tests. The most lopsided result is in Geekbench multicore, where the Intel part scores 5997 against AMD's 4473, a 34.1% advantage. That is a massive margin, indicating the desktop Intel chip with six physical cores has a significant throughput edge in this particular workload.

However, the Cinebench results tell a completely different story. The Ryzen 3 5400U wins all six Cinebench tests, with margins ranging from 7.6% to 8%. In Cinebench R15 multicore, AMD scores 942 versus Intel's 867, an 8% deficit for the i5-8600K. The R20 multicore test shows 3927 for AMD and 3616 for Intel, a 7.9% gap. R23 multicore follows the same pattern: 9350 for AMD, 8611 for Intel, again 7.9%. The single-core results are consistent: R15 single-core shows 132 versus 122 (7.6%), R20 single-core shows 554 versus 510 (7.9%), and R23 single-core shows 1320 versus 1215 (8%).

What is striking here is the consistency of the Cinebench margins. The AMD chip, despite having fewer cores (4 versus 6), beats the Intel part by nearly the same percentage across every Cinebench iteration. This suggests that Zen 3's architectural efficiency is carrying the workload, not raw core count. The Geekbench multicore result, however, flips the script entirely. Intel's two extra cores and higher boost clock appear to dominate in that specific benchmark environment.

The wins tally is 6 for AMD and 2 for Intel. But the magnitude matters: Intel's Geekbench multicore win is over four times larger than any single AMD margin. The average benchmark scores are close, with Intel at 2807 and AMD at 2765, a difference of only 1.5%. Both processors sit near the 50th percentile of all CPUs, Intel at 51 and AMD at 50. The overall picture is one of near-total parity, with workload-specific preferences determining the winner.

Architecture Differences

The architectural divide here is generational and fundamental. Intel Core i5-8600K uses Coffee Lake, a 14 nm design manufactured by Intel itself. It is a desktop part with 6 cores and 6 threads, meaning no hyper-threading. AMD Ryzen 3 5400U is built on Zen 3 architecture, codenamed Cezanne-U, manufactured by TSMC on a 7 nm process. It has 4 cores and 8 threads, enabling simultaneous multithreading.

The process node difference is significant: 14 nm versus 7 nm. AMD's smaller node, combined with the newer Zen 3 microarchitecture, explains much of the performance-per-clock advantage visible in the Cinebench results. AMD also lists 10,700 million transistors on a 180 mm² die, while Intel's transistor count and die size are not recorded in the database. The AMD chip is a mobile part with a 15 W TDP, whereas Intel's desktop chip draws 95 W. This power envelope disparity is enormous, yet the Ryzen still wins most benchmarks, evidence of its efficiency.

Cache configurations differ as well. Both have 64 KB of L1 per core, but AMD provides 512 KB of L2 per core versus Intel's 256 KB. L3 cache is 8 MB shared on AMD versus 9 MB shared on Intel. Memory bandwidth favors AMD at 51.2 GB/s versus Intel's 42.7 GB/s, despite both using dual-channel DDR4. PCIe lanes also differ: Intel offers Gen 3 with 16 lanes, while AMD provides Gen 3 with 8 lanes.

Integrated graphics are different: Intel uses UHD Graphics 630, AMD uses Radeon Vega 6. The Intel chip has an unlocked multiplier, making it overclockable, while the AMD part is locked. Intel's market segment is desktop, AMD's is mobile. Intel was released in October 2017 and is end-of-life, while AMD arrived in January 2021 and remains active. Intel's socket is Socket 1151, AMD uses Socket FP6. Intel's launch MSRP was $257; AMD's launch MSRP is not recorded.

FAQ

Q: Which processor wins the majority of benchmark tests?

A: The AMD Ryzen 3 5400U wins 6 out of 8 head-to-head benchmarks, while the Intel Core i5-8600K wins 2.

Q: How large is Intel's biggest benchmark victory?

A: In Geekbench multicore, Intel scores 5997 versus AMD's 4473, a 34.1% advantage. That is the largest delta in any test.

Q: What is the margin in Cinebench R23 multicore?

A: AMD scores 9350, Intel scores 8611, giving AMD a 7.9% lead.

Q: Do both processors support DDR4 memory?

A: Yes, both support DDR4 in dual-channel configuration. AMD has a higher memory bandwidth at 51.2 GB/s versus Intel's 42.7 GB/s.

Q: Is the Intel processor overclockable?

A: Yes, the Intel Core i5-8600K has an unlocked multiplier. The AMD Ryzen 3 5400U does not.

Q: Which chip has more physical cores?

A: Intel has 6 cores, AMD has 4 cores. However, AMD has 8 threads versus Intel's 6, due to simultaneous multithreading.

Specification Differences

| Specification | Intel Core i5-8600K | AMD Ryzen 3 5400U |

|---------------|---------------------|-------------------|

| Cores | 6 | 4 |

| Threads | 6 | 8 |

| Base Clock | 3.60 GHz | 2.60 GHz |

| Boost Clock | 4.30 GHz | 4.00 GHz |

| TDP | 95 W | 15 W |

| Socket | Intel Socket 1151 | AMD Socket FP6 |

| Architecture | Coffee Lake | Zen 3 |

| Codename | Coffee Lake | Cezanne-U |

| Process Node | 14 nm | 7 nm |

| Foundry | Intel | TSMC |

| Transistors | Not recorded | 10,700 million |

| Die Size | Not recorded | 180 mm² |

| L2 Cache | 256 KB (per core) | 512 KB (per core) |

| L3 Cache | 9 MB (shared) | 8 MB (shared) |

| Memory Bandwidth | 42.7 GB/s | 51.2 GB/s |

| PCIe | Gen 3, 16 Lanes | Gen 3, 8 Lanes |

| Integrated Graphics | UHD Graphics 630 | Radeon Vega 6 |

| Market Segment | Desktop | Mobile |

| Production Status | End-of-life | Active |

| Release Date | 2017-10-04 | 2021-01-11 |

| Launch MSRP | $257 | Not recorded |

| Multiplier Unlocked | Yes | No |

| Part Number | SR3QU | 100-000000288 |

The Verdict

The data shows two processors that are statistically inseparable in average performance: Intel at 2807, AMD at 2765, a 1.5% difference. Both sit at essentially the same percentile of all CPUs, Intel at 51, AMD at 50. The choice between them depends entirely on workload priorities.

The AMD Ryzen 3 5400U is the better pick for Cinebench-style rendering tasks. It wins every single Cinebench test, from R15 through R23, in both single-core and multicore modes. It does this while consuming only 15 W of power compared to Intel's 95 W, and it does it with two fewer physical cores. For anyone running continuous multi-threaded workloads, the Ryzen's efficiency and consistent 7.6% to 8% margins make it the clear data-driven choice.

The Intel Core i5-8600K earns its recommendation for Geekbench-centric workloads. Its 34.1% multicore lead and 6.7% single-core lead in Geekbench are substantial. For users whose software correlates with Geekbench scores, the Intel part offers a significant performance advantage. It also has twice the PCIe lanes (16 versus 8) and an unlocked multiplier for overclocking, though the database does not include overclocking benchmark results.

The mobile versus desktop distinction is critical. The Ryzen 3 5400U is a mobile processor with a 15 W TDP, designed for laptops. The i5-8600K is a desktop processor with a 95 W TDP. They are not interchangeable platforms. The data suggests that if you need a mobile chip that outperforms a six-core desktop part from 2017 in Cinebench, the Ryzen 3 5400U is exceptional. If you need a desktop chip with strong Geekbench multicore performance and overclocking headroom, the i5-8600K, despite being end-of-life, remains competitive.

The production status difference matters: AMD is active and current, Intel is end-of-life. For new system builders, the Ryzen 3 5400U is the only one still in production. The i5-8600K launched at $257 in 2017, but no current pricing data is available. The final verdict: choose AMD for Cinebench workloads and efficiency, choose Intel for Geekbench workloads and overclocking. The overall average scores are too close to declare a universal winner.