AMD Ryzen 5 7640U vs AMD Ryzen 5 8400F Comparison

The Verdict

The benchmark data presents an unusually one-sided comparison. The AMD Ryzen 5 8400F wins every single recorded head-to-head test, 17 out of 17, with no wins for the Ryzen 5 7640U. The 8400F is the clear choice for anyone building a desktop system where sustained performance and higher power delivery are acceptable. The 7640U, despite being a mobile part with a 15 W TDP, remains competitive in single-threaded workloads but falls behind in every measured category.

The data suggests the 8400F is the better processor for multi-core rendering, encryption, compression, and general productivity. Its average benchmark score of 25005 places it in the 77th percentile of all CPUs, while the 7640U sits at 25485 and the 78th percentile. Despite the 8400F having a lower average score, the head-to-head deltas show it dominating the 7640U in every specific test. The 7640U is the only option for mobile users, as it is the sole chip with integrated graphics and a mobile socket. The 8400F is a desktop part with no integrated graphics, so it requires a discrete GPU. The choice is not about performance alone; it is about platform and power constraints.

Architecture Differences

Both processors share the same Zen 4 architecture and the Phoenix codename, fabricated by TSMC on a 4 nm process node. The die size is identical at 178 mm², and the transistor count is the same at 25,000 million. Both have 6 cores and 12 threads, with a 16 MB shared L3 cache, 1 MB L2 per core, and 64 KB L1 per core. The memory support is DDR5 dual-channel in both cases, but the 7640U offers a higher memory bandwidth of 89.6 GB/s compared to the 8400F's 83.2 GB/s.

The critical differences lie in the platform and power envelope. The 7640U is a mobile processor with a 15 W TDP, designed for AMD Socket FP8, while the 8400F is a desktop processor with a 65 W TDP, using AMD Socket AM5. The 8400F has a higher base clock of 4.20 GHz versus 3.50 GHz, but a lower boost clock of 4.70 GHz versus 4.90 GHz. The 7640U includes the Radeon 760M integrated graphics, whereas the 8400F has no integrated graphics. The 7640U supports ECC memory, while the 8400F does not. The 8400F has an unlocked multiplier, while the 7640U does not. Both use PCIe Gen 4 with 20 lanes from the CPU.

These architectural differences explain the performance gap. The 8400F can draw more power and sustain higher clocks across all cores, which directly benefits multi-threaded workloads. The 7640U's higher boost clock suggests it can reach a higher peak on a single core, but the data shows the 8400F still wins in single-threaded tests, likely due to sustained power delivery. The 7640U's integrated graphics and lower TDP make it suitable for thin-and-light laptops, while the 8400F is a desktop part that relies on a separate GPU.

Where Each One Wins

Based on the recorded data, the 8400F wins every category. The largest deltas are in passmark extended instructions, where the 8400F leads by 23.3%, and passmark data compression, with a 16.7% lead. The smallest deltas are in passmark integer math, at 4.8%, and passmark single thread, at 4.4%. The 8400F also leads in all Cinebench tests by a consistent 14% margin, except for the R15 single-core test, where it leads by 13.9%.

The 7640U does not win any benchmark. However, its role is distinct. It is the only processor with integrated graphics, making it suitable for systems without a discrete GPU. Its 15 W TDP and mobile socket position it for laptops and compact devices where power efficiency is paramount. The 8400F, with its 65 W TDP and desktop socket, is designed for performance-oriented desktop builds. The data shows the 8400F is faster, but the 7640U is the only choice for mobile form factors.

The 8400F's wins in Cinebench R23 multi-core (20851 versus 17936) and single-core (2943 versus 2532) indicate it handles both heavily threaded and lightly threaded workloads better. The passmark multithread score of 24389 versus 21115 reinforces the multi-core advantage. For users who need maximum performance in a desktop, the 8400F is the superior option. For users who need a mobile processor with integrated graphics, the 7640U is the only option.

FAQ

Q: Which processor is faster in single-threaded performance?

A: The Ryzen 5 8400F wins in every single-threaded benchmark. It scores 296 in Cinebench R15 single-core versus 255, 1236 in R20 versus 1063, 2943 in R23 versus 2532, and 3685 in PassMark single-thread versus 3524.

Q: Does the Ryzen 5 7640U have integrated graphics?

A: Yes, the 7640U includes the Radeon 760M integrated graphics. The 8400F has no integrated graphics, so it requires a separate graphics card.

Q: What is the TDP difference between the two?

A: The 7640U has a TDP of 15 W, while the 8400F has a TDP of 65 W. This higher power budget for the 8400F contributes to its sustained performance advantage.

Q: Which processor supports ECC memory?

A: The 7640U supports ECC memory, while the 8400F does not.

Q: Which processor has a higher boost clock?

A: The 7640U has a higher boost clock of 4.90 GHz, while the 8400F boosts to 4.70 GHz. Despite this, the 8400F still wins all single-threaded benchmarks.

Q: Are both processors based on the same architecture?

A: Yes, both use the Zen 4 architecture with the Phoenix codename, are manufactured on a 4 nm TSMC process, and have the same 6-core, 12-thread configuration with 16 MB of L3 cache.

Head-to-Head Benchmarks

The 8400F dominates the Cinebench suite. In Cinebench R15 multi-core, it scores 2101 against the 7640U's 1807, a 14% advantage. The single-core R15 test shows 296 versus 255, a 13.9% lead. In Cinebench R20, the multi-core score is 8757 versus 7533, and the single-core score is 1236 versus 1063, both 14% leads. Cinebench R23 shows the same pattern: 20851 versus 17936 in multi-core and 2943 versus 2532 in single-core, both 14% ahead.

The PassMark suite reveals a broader spread. The largest gap is in extended instructions, where the 8400F scores 22175 against 17019, a 23.3% lead. Data compression shows 288158 versus 240032, a 16.7% advantage. Random string sorting is 34604 versus 29382, a 15.1% lead. Find prime numbers is 89 versus 74, a 16.9% lead. Multithread is 24389 versus 21115, a 13.4% lead. Physics is 1332 versus 1169, a 12.2% lead. Floating point math is 46217 versus 41093, an 11.1% lead. Data encryption is 16646 versus 14954, a 10.2% lead. The smallest gaps are in integer math, 74021 versus 70483, a 4.8% lead, and single-thread, 3685 versus 3524, a 4.4% lead.

The 8400F also has additional benchmark data that the 7640U lacks, including 3DMark tests. These show scores of 6091 for 16 threads, 1874 for 2 threads, 3563 for 4 threads, 5275 for 8 threads, 6165 for max threads, and 951 for single thread. These results further illustrate the 8400F's multi-threaded capability, though no direct comparison is possible since the 7640U has no recorded 3DMark scores.

Specification Differences

The two processors differ in several key specifications. The 7640U is part of the 7000 series, while the 8400F is part of the 8000 series. The 7640U has a base clock of 3.50 GHz and a boost clock of 4.90 GHz, while the 8400F has a base clock of 4.20 GHz and a boost clock of 4.70 GHz. The TDP differs significantly: 15 W for the 7640U versus 65 W for the 8400F.

The socket is a major difference: the 7640U uses AMD Socket FP8, while the 8400F uses AMD Socket AM5. The 7640U supports ECC memory, while the 8400F does not. The 7640U has integrated Radeon 760M graphics, while the 8400F has N/A for integrated graphics. The 7640U has a locked multiplier, while the 8400F has an unlocked multiplier. The 7640U has a memory bandwidth of 89.6 GB/s, while the 8400F has 83.2 GB/s.

The 7640U was released on 2023-05-02, while the 8400F was released on 2024-03-31. The 8400F has a launch MSRP of $170. The 7640U has no recorded launch MSRP. The 7640U has three part numbers (100-000001106 (FP7r2), 100-000001109 (FP7), 100-000001132 (FP8)), while the 8400F has one (100-000001591). Both have the same process node, foundry, transistor count, die size, cache structure, memory type, memory bus, PCIe lanes, architecture, codename, generation, and market segment differs only by mobile versus desktop.