The Intel Core i7-8559U is a quad-core SoC for notebooks based on the Coffee Lake architecture and was announced in April 2018. Compared to its predecessor Core i7-7567U, the CPU is now a quad-core with Hyperthreading support for the execution of up to 8 threads simultaneously. The base frequency is 2.7 GHz, but the Turbo goes all the way up to 4.5 GHz. It is also equipped with an Intel Iris Plus Graphics 655 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 i5 models with eDRAM and 28 Watts, the i5-8559U features 8 MB smart cache and the fastest 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
Clocked at up to 4.5 GHz, the Core i7-8559U is currently the fastest quad core ULV from Intel. Whether these speeds can be maintained in practice depends on the cooling capabilities of the laptop, but the performance should be above the Core i7-8650U due to the increased TDPConsidering the clocks of the Core i7-8559U, its performance should be between the 15W models Core i5-8350U and Core i7-8550U. The i5-8259U should still be faster than the i7-8550U in practice thanks to the increased TDP, especially during sustained workloads.
Graphics
The integrated Intel Iris Plus 655 Graphics is the GT3e model of the Coffee Lake GPU (Intel Gen. 9.5). It has 48 Execution Units running at 300-1200 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 28 Watts, which can be reduced to 23 Watts (cTDP Down) depending on the usage scenario. The TDP is pretty high compared to the common 15-Watt TDP for quad-core processors, but allows a better utilization of CPU and GPU Turbo.
The Intel Core i5-1230U is a 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 to 4.4 GHz on the performance cluster and 0.7 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 similar Core i5-1240U, the 1230U offers a lower base CPU clock speed and only "Essentials" vPro management features.
Performance
Compared to the old 7 Watt Comet Lake-Y series (like the i7-10510Y), the performance should be clearly better thanks to the 10 cores and the improved architecture of the P-cores. Compared to the 15 W U-series (like the similar specified Core i5-1235U) the sustained performance will be clearly limited by the 9 Watt TDP. As always, the performance will also greatly depend on the cooling solution, especially for fanless laptops and tablets.
Features
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 0.85 GHz.
The CPU is rated at 9 W base power (TDP, PL1) and 29 W max. Turbo power (PL2) and the whole SoC is manufactured on a 10nm process at Intel, which is known as Intel 7.
- Range of benchmark values for this graphics card - Average benchmark values for this graphics card * Smaller numbers mean a higher performance 1 This benchmark is not used for the average calculation
v1.34
log 21. 01:16:58
#0 ran 0s before starting gpusingle class +0s ... 0s
#1 checking url part for id 10072 +0s ... 0s
#2 checking url part for id 14110 +0s ... 0s
#3 redirected to Ajax server, took 1761002218s time from redirect:0 +0s ... 0s
#4 did not recreate cache, as it is less than 5 days old! Created at Sun, 19 Oct 2025 05:20:51 +0200 +0s ... 0s
#5 composed specs +0.005s ... 0.005s
#6 did output specs +0s ... 0.005s
#7 getting avg benchmarks for device 10072 +0.004s ... 0.009s
#8 got single benchmarks 10072 +0.005s ... 0.014s
#9 getting avg benchmarks for device 14110 +0.004s ... 0.017s
#10 got single benchmarks 14110 +0.006s ... 0.024s
#11 got avg benchmarks for devices +0s ... 0.024s
#12 min, max, avg, median took s +0.04s ... 0.063s