Intel Core i5-1250P vs Intel Core i5-8257U

Intel Core i5-1250P

The Intel Core i5-1250P is a mid-range Alder Lake-P family SoC designed for use in ultra-light, ultra-thin (yet actively cooled) laptops. It was announced in early 2022 and it has 4 performance cores, as opposed to the 6 cores of the top-of-the-line i7-1280P (P-cores, Golden Cove architecture) mated to 8 efficient cores (E-cores, Gracemont architecture). The i5's P-cores are Hyper-Threading-enabled for a total of 16 threads when combined with its E-cores. The clock speeds range from 1.7 GHz to 4.4 GHz for the performance cluster and 1.2 GHz to 3.3 GHz for the efficient cluster. The shortcomings of this processor as compared with the slightly faster Core i5-1260P include the smaller L3 cache, slower iGPU model, lower clock speeds. Full vPro feature set is enabled in the case of this i5, though ("Enterprise" tier, allowing for remote device management).

Architecture

The i5 is a continuation of Intel's efforts to use the ARM-developed big.LITTLE technology for its own benefit. A single "little" Alder Lake core is supposed to be as fast as a Skylake core (as found in the venerable Core i7-6700HQ among other options) which is six years old at this point. All of Core i5-1250P's CPU cores enjoy access to 12 MB of L3 cache. The integrated memory controller supports various memory types up to LPDDR5-5200, DDR5-4800, LPDDR4x-4267 or DDR4-3200; Intel recommends using no more than 64 GB, for reference. Just like the other 12th Gen Intel Core processors, this Core i5 comes with the Thread Director which is a new functionality designed to help Windows 11 decide which cores to use for what workload for best performance and efficiency possible. Hardware acceleration of AI algorithms is supported via GNA 3.0 and DL Boost (via AVX2). The alluringly fast PCI-Express 5.0 spec has not found its way into Alder Lake P processors, so users will have to be content with PCI-Express 4.0 for the time being. Four PCI-Express 4 lanes allow for a read/write rate of up to 7.9 GB/s, provided a suitably fast NVMe SSD is used.

Please note this is not a user-replaceable CPU. It gets permanently soldered on to the motherboard (FCBGA1744 socket interface).

Performance

The average 1250P in our database nearly matches the Ryzen 5 5500U and the Ryzen 5 PRO 6650U in multi-thread performance, trailing behind the Core i5-1240P just slightly. This is a great CPU for nearly all tasks imaginable, as long as one does not expect it to be as fast as the mighty Core i7-12700H.

Your mileage may vary depending on how high the Power Limits are and how competent the cooling solution of your system is. The latter is really important as a single Golden Cove core can eat more than 20 W when under heavy load.

Graphics

The built-in graphics adapter in the form of the 80 EU Iris Xe running at up to 1.4 GHz has seen little change from what was built into certain 11th Gen Tiger Lake UP3 processors, like a Core i5-1135G7, which is hardly a downside as this iGPU is loaded with modern features, AV1 video decoding capability and SUHD 4320p monitor support included. The Xe isn't a stranger to a bit of casual gaming; that said, your mileage may vary depending on how high the Power Limits are and how capable the cooling solution of a laptop is. Expect something close to NVIDIA's MX250 or in other words, acceptable framerates in most games when playing at 1080p / Low settings. Fast RAM is a prerequisite for decent performance as the Xe has to make do with no dedicated video memory.

Power consumption

The i5's base power consumption (also known as the default TDP or Power Limit 1) is 28 W; its maximum Turbo power consumption (also known as the PL2) is not supposed to exceed 64 W. As for the "Minimum Assured" power consumption, Intel's guidelines mention 20 W. All in all, an active cooling solution is a must for a CPU like this.

The i5-1250P is built with Intel's fourth-gen 10 nm manufacturing process marketed as Intel 7 for decent, as of late 2022, energy efficiency. Despite that, the i5 is more power-hungry than certain 7 nm U-class AMD Ryzen 5000 chips delivering similar, or even higher, performance.

Intel Core i5-8257U

The Intel Core i5-8257U is a quad-core SoC for notebooks based on the Coffee Lake architecture that was announced in the new entry level MacBook Pro 13 in mid 2019. Compared to its predecessor, the CPU is now a quad-core with Hyperthreading support for the execution of up to 8 threads simultaneously. The base frequency is only 1.4 GHz, but the Turbo goes all the way up to 3.9 GHz. It is also equipped with an Intel Iris Plus Graphics 645 GPU with 128 MB eDRAM, a dual-channel memory controller (DDR4) as well as VP9 and H.265 video decoding as well as encoding. The chip is still manufactured in a 14nm process with FinFET transistors.

Compared to faster Core i7-8557U model with eDRAM and 15 Watts, the i5-8257U only features 6 MB smart cache and the slowest clock of the Iris Plus GPU.

Architecture

Intel basically uses the same micro architecture compared to Kaby Lake, so the per-MHz performance does not differ. The manufacturer only reworked the Speed Shift technology for faster dynamic adjustments of voltages and clocks, and the improved 14nm process allows much higher frequencies combined with better efficiency than before.

Performance

Thanks to the relative high Turbo Boost clock, the single thread performance should be very good, but still behind the faster i7 model. The short burst all core performance is clearly better compared to the old dual core predecessors thanks to the additional cores. In sustained workloads, the performance is usually limited by the TDP and cooling. In these workloads the difference to the Core i7 should be also smaller.

Graphics

The integrated Intel Iris Plus 645 Graphics is the GT3e model of the Coffee Lake GPU (Intel Gen. 9.5). It has 48 Execution Units running at 300-1050 MHz and the performance is comparable to a GeForce 930M or 940MX thanks to fast eDRAM cache. However, there aren't any significant improvements compared to the old Iris Plus 650, so modern games can often not be played smoothly or only at the lowest or medium settings, respectively.

Contrary to Skylake, Kaby lake now also supports H.265/HEVC Main 10 with a 10-bit color depth as well as Google's VP9 codec. The dual-core Kaby Lake processors announced in January should also support HDCP 2.2.

Power Consumption

The chip is manufactured in an improved 14nm++ process with FinFET transistors, which improves the efficiency even further. Intel specifies the TDP with 15 Watts and therefore suited for thin and light laptops.