Qualcomm Snapdragon 8cx Gen 3 vs Intel Core i5-1235U

Qualcomm Snapdragon 8cx Gen 3

The Qualcomm Snapdragon 8cx Gen 3 Compute Platform is an ARM based SoC for Windows laptops. It integrates four big ARM Cortex-X1 performance cores (up to 3 GHz) and four smaller ARM Cortex-A78 with up to 2.4 GHz.

The Compute Platform also integrates a Snapdragon X62 5G modem with up to 10 Gbps download and 316 Mbps upload. The integrated WLAN modem supports Wi-Fi 6E (2x2) and the satellite positioning system supports BeiDou, Galileo, GLONASS, GPS, QZSS, and SBAS. The integrated video engine supports H.264, H.265, and VP9 decoding in 4K 120fps.

The performance should be around 85% faster for the CPU and 60% faster for the GPU compared to the previous generation (Snapdragon 8cx Gen 2).

The chip is produced in the modern 5nm process at Samsung (5LPE) and designed for fanless laptops (7 to 9 Watt TDP range).

Intel Core i5-1235U

The Intel Core i5-1235U is a mid-range mobile CPU for thin and light laptops based on the Alder Lake architecture. It was announced in early 2022 and offers 2 performance cores (P-cores, Golden Cove architecture) and 8 efficient cores (E-cores, Gracemont architecture). The P-cores support Hyper-Threading leading to 12 supported threads when combined with the E-cores. The clock rate ranges from 1.3 to 4.4 GHz on the performance cluster and 0.9 to 3.3 GHz on the efficient cluster. The performance of the E-cores should be similar to old Skylake cores (compare to the Core i7-6700HQ). All cores can use up to 12 MB L3 cache. Compared to the i5-1245U, the 1235U offers lower base clock speeds and only "Essentials" vPro management features. Compared to the P-series (28W) or H-series (45W), the 15W TDP may limit the sustained performance.

Performance

The average 1235U in our database is in the same league as the Ryzen 5 PRO 5650U and also, surprisingly enough, the i7-1250U and the i7-1260U, as far as multi-thread benchmark scores are concerned. This is a very respectable result, as of mid 2023.

Thanks to its decent cooling solution and a long-term CPU power limit of 27 W, the Beelink SEi12 is among the fastest systems built around the 1235U that we know of. It can be twice as fast in CPU-bound workloads as the slowest system featuring the same chip in our database, as of August 2023.

Architecture

The integrated memory controller supports various memory types up to DDR5-4800, DDR4-3200, LPDDR5-5200, and LPDDR4x-4267. The Thread Director (in hardware) can support the operating system to decide which thread to use on the performance or efficient cores for the best performance. For AI tasks, the CPU also integrates GNA 3.0 and DL Boost (via AVX2). Quick Sync in version 8 is the same as in the Rocket Lake CPUs and supports MPEG-2, AVC, VC-1 decode, JPEG, VP8 decode, VP9, HEVC, and AV1 decode in hardware. The CPU only supports PCIe 4.0 (x8 for a GPU and two x4 for SSDs).

The integrated graphics card is based on the Xe-architecture and offers 80 of the 96 EUs (Execution Units) operating at up to 1.2 GHz.

Power consumption

This ULV processor has a Base power consumption of 15 W (also known as the long-term power limit), with 55 W being its maximum Intel-recommended Turbo power consumption. Both values are too high to allow for passively cooled designs.

Core i5-1235U is manufactured on Intel's fourth-gen 10 nm process marketed as Intel 7 for decent, as of mid-2022, energy efficiency.