Core i5-10400F vs Core i7-1255U

The Core i5-10400F packs 6 cores / 12 threads, while the Core i7-1255U offers 10 cores / 12 threads — the Core i7-1255U has 4 more cores. Boost clocks reach 4.3 GHz on the Core i5-10400F versus 4.7 GHz on the Core i7-1255U — a 8.9% clock advantage for the Core i7-1255U (base: 2.9 GHz vs 1.7 GHz). The Core i5-10400F uses the Comet Lake (2020−2025) architecture (14 nm), while the Core i7-1255U uses Alder Lake-U (2022) (Intel 7 nm). In PassMark, the Core i5-10400F scores 13,029 against the Core i7-1255U's 13,128 — a 0.8% lead for the Core i7-1255U. Geekbench 6 single-core — the metric most relevant to gaming — records 1,454 vs 1,809, a 21.8% lead for the Core i7-1255U that directly translates to higher frame rates. Both processors carry 12 MB (total) of L3 cache.

The Core i5-10400F uses the LGA1200 socket (PCIe 3.0), while the Core i7-1255U uses FCBGA1744 (PCIe 5.0) — making them incompatible on the same motherboard. Maximum memory speed reaches DDR4-2666 on the Core i5-10400F versus DDR5-4800 on the Core i7-1255U — the Core i7-1255U supports 22.2% faster memory, which can translate to measurable gains in memory-sensitive workloads. The Core i5-10400F supports up to 128 GB of RAM compared to 64 GB — 66.7% more capacity for professional workloads. Both feature 2-channel memory with ECC support. PCIe lanes: 16 (Core i5-10400F) vs 20 (Core i7-1255U) — the Core i7-1255U offers 4 more lanes for additional GPUs or NVMe drives. Chipset compatibility: H410,B460,H470,Z490,H510,B560,H570,Z590 (Core i5-10400F) and Alder Lake-U (Core i7-1255U).

Neither processor supports overclocking. Virtualization support: VT-x, VT-d (Core i5-10400F) vs VT-x, VT-d, EPT (Core i7-1255U). The Core i7-1255U includes integrated graphics (Iris Xe Graphics 96EU), while the Core i5-10400F requires a dedicated GPU. Primary use case: Core i5-10400F targets Gaming, Core i7-1255U targets Mainstream Laptop. Direct competitor: Core i5-10400F rivals Ryzen 5 3600; Core i7-1255U rivals Ryzen 7 6800U.