AMD Athlon X4 840 vs Intel Celeron N5100 Comparison

The benchmark data places the Intel Celeron N5100 and AMD Athlon X4 840 in the same performance tier, with the AMD part holding a narrow but consistent edge across every tested workload. The Athlon X4 840 wins all five head-to-head Cinebench comparisons, yet the largest margin is only 1.2%, making the performance difference effectively negligible for most real-world tasks. The Celeron N5100 is the clear choice for low-power and mobile systems, given its drastically lower 6W TDP and integrated graphics, while the Athlon X4 840 suits desktop builds where its higher 65W power envelope and unlocked multiplier are acceptable trade-offs for a marginal performance lead.

The Verdict

Choose the AMD Athlon X4 840 if you prioritize raw multi-threaded throughput and plan to use a discrete GPU. Its benchmark scores are consistently ahead: it leads by 1.1% in Cinebench R15 multi-core, 0.8% in R20 multi-core, and 0.8% in R23 multi-core. The single-core advantage is similarly small, at 1.2% in R20 and 1.0% in R23. The Athlon also offers an unlocked multiplier for overclocking, 16 PCIe Gen 3 lanes versus the Celeron's 8, and a higher 3.80 GHz boost clock. However, this comes at a 65W TDP and requires a discrete graphics solution, as it has no integrated GPU.

Choose the Intel Celeron N5100 if power efficiency and integrated graphics are non-negotiable. Its 6W TDP is less than one-tenth of the Athlon's, making it ideal for fanless or battery-powered designs. The Celeron includes UHD Graphics 24EU, eliminating the need for a separate graphics card. Despite losing every benchmark by less than 1.2%, the Celeron's performance is close enough that the power savings and platform simplicity outweigh the tiny performance deficit in most productivity scenarios. It also supports newer DDR4/LPDDR4 memory and has a smaller die size of 63.8 mm² versus 245 mm².

The data does not support a performance-based verdict. Both processors sit at the 26th percentile among all CPUs, and their average benchmark scores are nearly identical: 966 for the Celeron versus 975 for the Athlon. The Athlon is the winner on paper, but the margin is within run-to-run variance. The decision hinges entirely on platform requirements: the Celeron for embedded/mobile efficiency, the Athlon for desktop flexibility with overclocking.

FAQ

Q: Which processor is faster in multi-core Cinebench tests?

A: The AMD Athlon X4 840 wins all three multi-core tests. It scores 285 versus 282 in Cinebench R15, 1189 versus 1179 in R20, and 2833 versus 2809 in R23. The largest multi-core delta is 1.1% in R15.

Q: Is the Intel Celeron N5100 more power-efficient?

A: Yes, by a wide margin. The Celeron has a 6W TDP, while the Athlon X4 840 has a 65W TDP. This makes the Celeron dramatically more suitable for low-power systems despite its slightly lower performance.

Q: Do both processors have integrated graphics?

A: No. The Intel Celeron N5100 includes UHD Graphics 24EU, while the AMD Athlon X4 840 has no integrated graphics, requiring a discrete GPU for display output.

Q: Can the AMD Athlon X4 840 be overclocked?

A: Yes, the Athlon X4 840 has an unlocked multiplier, allowing overclocking. The Celeron N5100 does not have an unlocked multiplier.

Q: What memory types do they support?

A: The Celeron N5100 supports DDR4 and LPDDR4 memory, while the Athlon X4 840 supports only DDR3. Both use a dual-channel memory bus, but the Celeron's bandwidth is higher at 46.9 GB/s versus 34.1 GB/s for the Athlon.

Q: How do their single-core scores compare?

A: The Athlon wins both single-core tests. It scores 168 versus 166 in Cinebench R20 (a 1.2% lead) and 400 versus 396 in Cinebench R23 (a 1.0% lead). These differences are negligible for single-threaded applications.

Architecture Differences

The two processors come from fundamentally different design eras and philosophies. The Intel Celeron N5100 uses the Tremont architecture on the Jasper Lake codename, built on a 10 nm process by Intel. It features a 63.8 mm² die and a shared 1.5 MB L2 cache plus a 4 MB shared L3 cache. Its cache hierarchy includes 64 KB of L1 per core. The Celeron is a mobile-focused part with a 6W TDP, reflecting its design for low-power devices.

The AMD Athlon X4 840 uses the Steamroller architecture on the Kaveri codename, manufactured by GlobalFoundries on a 28 nm process. This older design is significantly larger, with a 245 mm² die and 2,411 million transistors. It has 256 KB of L1 cache and 4 MB of L2 cache, but no L3 cache at all. The Athlon's 65W TDP and desktop market segment indicate a design prioritizing performance over efficiency.

Memory support diverges sharply. The Celeron supports DDR4 and LPDDR4 with a dual-channel bus and 46.9 GB/s bandwidth. The Athlon is limited to DDR3 with a dual-channel bus and 34.1 GB/s bandwidth. The Celeron also integrates UHD Graphics 24EU, while the Athlon has no GPU. PCIe connectivity differs as well: the Celeron offers Gen 3 with 8 CPU lanes, while the Athlon offers Gen 3 with 16 CPU lanes.

The production status of both is end-of-life, and neither supports ECC memory. The Celeron's process node advantage (10 nm versus 28 nm) and newer architecture explain its ability to deliver comparable performance at a fraction of the power draw. The Athlon's larger die and older node account for its higher power consumption and physical size.

Specification Differences

| Specification | Intel Celeron N5100 | AMD Athlon X4 840 |

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

| Base Clock | 1100.00 MHz | 3.10 GHz |

| Boost Clock | 2.80 GHz | 3.80 GHz |

| TDP | 6W | 65W |

| Socket | Intel BGA 1338 | AMD Socket FM2+ |

| Process Node | 10 nm | 28 nm |

| Foundry | Intel | GlobalFoundries |

| Die Size | 63.8 mm² | 245 mm² |

| Transistors | Not specified | 2,411 million |

| L1 Cache | 64 KB (per core) | 256 KB |

| L2 Cache | 1.5 MB (shared) | 4 MB |

| L3 Cache | 4 MB (shared) | None |

| Memory Support | DDR4, LPDDR4 | DDR3 |

| Memory Bandwidth | 46.9 GB/s | 34.1 GB/s |

| PCIe | Gen 3, 8 Lanes (CPU only) | Gen 3, 16 Lanes (CPU only) |

| Integrated Graphics | UHD Graphics 24EU | None |

| Multiplier Unlocked | No | Yes |

| Market Segment | Mobile | Desktop |

| Part Number | SRKGZ | AD840XYBJABOXAD840XYBI44JA |

Both processors have 4 cores and 4 threads, identical in this regard. The Celeron's boost clock is 2.80 GHz versus the Athlon's 3.80 GHz, a 1 GHz difference favoring AMD. The Athlon also has a higher base clock at 3.10 GHz versus 1.10 GHz. The Celeron's 4 MB L3 cache compensates partially for its smaller L2 cache. The Athlon's lack of L3 cache is offset by its larger 4 MB L2 pool.

Head-to-Head Benchmarks

The AMD Athlon X4 840 wins every single benchmark in the comparison, but the margins are consistently under 1.2%. In Cinebench R15 multi-core, the Athlon scores 285 against the Celeron's 282, a 1.1% lead. This is the largest performance gap in the entire dataset. In Cinebench R20 multi-core, the Athlon scores 1189 versus 1179, a 0.8% advantage. The R23 multi-core test shows a similar pattern: 2833 for AMD versus 2809 for Intel, again a 0.8% delta.

Single-core results follow the same trend but with slightly larger relative margins. The Athlon wins Cinebench R20 single-core with 168 points against 166, a 1.2% difference. In R23 single-core, the Athlon scores 400 versus 396, a 1.0% lead. These single-core deltas are actually larger than some multi-core deltas, indicating the Athlon's higher clock speeds (3.80 GHz boost versus 2.80 GHz) provide a consistent, if small, advantage across all thread counts.

The average benchmark scores reinforce this near-parity. The Celeron N5100 averages 966 points, while the Athlon X4 840 averages 975 points, a difference of less than 1%. Both processors occupy the 26th percentile among all CPUs, confirming they are direct competitors. The Celeron's nearest rivals include the Intel Xeon X5570 (avg 967, -0.1% delta) and AMD Ryzen 7 3700U (avg 968, -0.2%), while the Athlon's nearest rivals include the Intel Core i3-4130 (avg 975, 0% delta) and AMD A10-7870K (avg 975, 0% delta).

The data shows a clear winner in raw benchmark terms: the Athlon X4 840 takes all five head-to-head tests. However, the largest delta is 1.2%, which would not be perceptible in most applications. The Celeron's 46.9 GB/s memory bandwidth advantage and integrated GPU do not appear in these CPU-only Cinebench tests, meaning the real-world gap could narrow further in graphics or memory-intensive workloads.

Where Each One Wins

AMD Athlon X4 840 wins on raw CPU benchmarks. It is faster in all five Cinebench tests, with leads ranging from 0.8% to 1.2%. The Athlon also wins on overclocking potential due to its unlocked multiplier, allowing users to push beyond its 3.80 GHz boost clock. For desktop users with a discrete GPU, the Athlon's 16 PCIe Gen 3 lanes provide more bandwidth for graphics cards or NVMe storage compared to the Celeron's 8 lanes. Its higher 3.10 GHz base clock also means it will not downclock as aggressively under sustained loads.

Intel Celeron N5100 wins on power efficiency and platform integration. The 6W TDP versus 65W is a 59W difference, making the Celeron suitable for passive cooling, thin-and-light devices, or always-on systems. Its integrated UHD Graphics 24EU means no separate GPU is required, reducing system cost and complexity. The Celeron's 46.9 GB/s memory bandwidth exceeds the Athlon's 34.1 GB/s, which can benefit integrated graphics and memory-sensitive workloads. Its support for DDR4/LPDDR4 memory is a modern advantage over the Athlon's DDR3-only limitation.

For single-threaded tasks like web browsing or office productivity, the difference is marginal—the Athlon leads by just 1.0-1.2% in single-core tests. For multi-threaded rendering, the Athlon's lead is similarly small at 0.8-1.1%. The Celeron's smaller die (63.8 mm² versus 245 mm²) and newer 10 nm process indicate better manufacturing efficiency, while the Athlon's larger die and 28 nm process reflect an older, less efficient design.

The verdict from the data: the Athlon X4 840 is the benchmark champion, but the Celeron N5100 is the more sensible choice for any application where power draw or integrated graphics matter. Neither processor offers a meaningful performance advantage over the other, so the decision should be driven by platform needs rather than raw scores.