Core i7-1255U vs Core i5-11400T

The Core i7-1255U packs 10 cores / 12 threads, while the Core i5-11400T offers 6 cores / 12 threads — the Core i7-1255U has 4 more cores. Boost clocks reach 4.7 GHz on the Core i7-1255U versus 3.7 GHz on the Core i5-11400T — a 23.8% clock advantage for the Core i7-1255U (base: 1.7 GHz vs 1.3 GHz). The Core i7-1255U uses the Alder Lake-U (2022) architecture (Intel 7 nm), while the Core i5-11400T uses Rocket Lake (2021) (14 nm). In PassMark, the Core i7-1255U scores 13,128 against the Core i5-11400T's 13,034 — a 0.7% lead for the Core i7-1255U. Geekbench 6 single-core — the metric most relevant to gaming — records 1,809 vs 1,767, a 2.3% lead for the Core i7-1255U that directly translates to higher frame rates. Both processors carry 12 MB (total) of L3 cache.

The Core i7-1255U uses the FCBGA1744 socket (PCIe 5.0), while the Core i5-11400T uses LGA1200 (PCIe 4.0) — making them incompatible on the same motherboard. Maximum memory speed reaches DDR5-4800 on the Core i7-1255U versus DDR4-3200 on the Core i5-11400T — the Core i7-1255U supports 22.2% faster memory, which can translate to measurable gains in memory-sensitive workloads. The Core i5-11400T 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. Both provide 20 PCIe lanes. Chipset compatibility: Alder Lake-U (Core i7-1255U) and H510,B560,Z590,H470,Z490 (Core i5-11400T).

Neither processor supports overclocking. Only the Core i5-11400T supports AVX-512 instructions — important for machine learning and scientific applications. Both support VT-x, VT-d, EPT virtualization. Both include integrated graphics — Iris Xe Graphics 96EU (Core i7-1255U) and UHD 730 (Core i5-11400T) — useful as a fallback for troubleshooting or display output without a dedicated GPU. Primary use case: Core i7-1255U targets Mainstream Laptop, Core i5-11400T targets Productivity. Direct competitor: Core i7-1255U rivals Ryzen 7 6800U; Core i5-11400T rivals Core i5-11400.