Quick Verdict
A premium 28W mobile processor that combined high clock speeds with powerful Iris Plus graphics, delivering an excellent balance of CPU and GPU performance.
Overview
Launch
2018
Status
ActiveGeneration
8th Gen Core i7
Market
Mobile
The Intel Core i7-8559U is a specialized mobile processor launched in April 2018 as part of the 8th Generation Kaby Lake-U Refresh family. Designed primarily for Apple's MacBook Pro lineup, this chip operates at a higher 28-watt TDP compared to the standard 15W U-series processors. Built on the 14nm process, it features 4 cores and 8 threads. The increased power envelope allows for a significantly higher base clock of 2.7 GHz and a boost clock of up to 4.5 GHz. It includes 8MB of L3 cache and integrates Intel Iris Plus Graphics 655, which features 128MB of embedded DRAM (eDRAM) for enhanced graphical and computational performance. This makes the i7-8559U uniquely capable of handling light gaming and hardware-accelerated video editing without a dedicated GPU. While it runs warmer than standard ultrabook chips, its combination of high clock speeds and powerful integrated graphics makes it a sought-after option for compact, high-performance portable systems.
The Intel Core i7-8559U is an 8th Gen mobile processor operating at a 28W TDP. Featuring 4 cores, 8 threads, and boost speeds up to 4.5 GHz, it is significantly faster than standard 15W U-series chips.
Its standout feature is the Intel Iris Plus Graphics 655 with 128MB of eDRAM, providing excellent integrated graphical performance for a mobile chip.
Specifications
Performance
High clock speeds ensure excellent performance in office and creative apps.
Capable of running light VMs, though limited by 4 cores.
Iris Plus 655 allows for playable frame rates in older or well-optimized games.
28W TDP is efficient enough for laptops but warmer than 15W parts.
- •Iris Plus 655 is a major step up from UHD 620
- •eDRAM helps with texture loading
- •Can run macOS games smoothly
- •No dedicated AI hardware
- •eDRAM can be utilized for certain compute workloads
Architecture
14nm
Process Node
Kaby Lake-R
Codename
4C / 8T
Core Config
8 MB
L3 Cache
28 W
TDP
Architecture Overview
The Core i7-8559U utilizes the Kaby Lake Refresh microarchitecture, but distinguishes itself through a 28-watt TDP configuration and enhanced integrated graphics. Built on Intel's 14nm process, it features 4 cores and 8 threads. The higher TDP allows the architecture to maintain a 2.7 GHz base clock, significantly higher than the 1.8 GHz of its 15W counterpart. The most critical architectural feature is the integration of Intel Iris Plus Graphics 655, which includes 48 execution units and 128MB of embedded DRAM (eDRAM). This eDRAM acts as a high-speed cache for both the GPU and the CPU, drastically reducing memory latency and boosting graphical performance. The architecture supports dual-channel DDR4 memory at 2400 MT/s. By combining high sustained CPU frequencies with a powerful integrated GPU solution, this architecture was specifically tailored to meet the demands of premium, compact laptops that required strong compute and graphical capabilities without the space for a discrete GPU.
CPU Design
4 cores with Hyper-Threading.
Memory Subsystem
Dual-channel DDR4 support.
PCIe & I/O
12 PCIe 3.0 lanes.
Overclocking
Locked multiplier.
- Double the cores (4 vs 2)
- Higher boost clock
- Larger L3 cache
Key Highlights
- High 4.5 GHz boost clock
- Iris Plus Graphics with 128MB eDRAM
- 28W TDP allows good sustained performance
- Excellent single-core speed
- Runs warmer than 15W U-series chips
- Soldered to motherboard
- 14nm process is outdated
- Limited to older platforms
History
Introduced on April 5th, 2018, the Core i7-8559U was a specialized processor designed to bridge the gap between low-power ultrabook chips and high-performance mobile processors. It was primarily deployed in Apple's 2018 Mac Mini and the 13-inch MacBook Pro, offering a 28W power envelope that allowed for higher sustained clock speeds. The inclusion of Intel Iris Plus Graphics 655 with 128MB of eDRAM was a defining feature, providing a significant graphical boost over the standard UHD 620 found in 15W chips.
This processor represented Intel's strategy of utilizing eDRAM to enhance integrated graphics performance before the transition to dedicated Xe graphics architectures. While it delivered excellent performance for its size, it was eventually overshadowed by Apple's transition to its own M-series silicon. Nevertheless, the i7-8559U remains a notable chip in Intel's history, showcasing the potential of high-end integrated graphics in compact form factors.
Improvements over Previous Generation
- Double the cores (4 vs 2)
- Higher boost clock
- Larger L3 cache
Alternatives & Competitors
Should You Buy It?
Recommended for the right buyer
If you are considering a laptop with the Intel Core i7-8559U, you are likely looking at a used MacBook Pro or a premium NUC. This processor remains highly capable for everyday productivity, programming, and light 1080p video editing. The inclusion of Iris Plus graphics with eDRAM provides a noticeable boost in graphical tasks compared to standard U-series chips. It is an excellent choice for users who need a compact, moderately powerful machine without paying the premium for Apple Silicon. However, be aware that it is an Intel-based Mac, meaning it will eventually lose macOS support. Avoid this processor if you need to run modern AAA games or heavy 3D rendering workloads. It is best purchased at a discount for general use and legacy software.
Avoid if…
- You need Windows on ARM
- You want the latest macOS features
- You need to run heavy 4K video timelines
Use Cases
Interesting Facts
It is essentially a higher-binned i7-8550U with better graphics.
It includes 128MB of eDRAM for the integrated GPU.
It was heavily featured in the 2018 Mac Mini and 13-inch MacBook Pro.
The 28W TDP allows for a much higher base clock than standard U-series.
It supports Intel Quick Sync Video for fast hardware encoding.
The chip uses the BGA 1356 socket.
Its integrated graphics are Iris Plus 655, not the standard UHD 620.
It supports dual-channel DDR4 memory up to 2400 MT/s.
The processor is locked and cannot be overclocked.
It was one of the last Intel processors to use eDRAM before Xe graphics.
People Also Ask
Is the i7-8559U good for gaming?
It is surprisingly capable for light gaming thanks to its Iris Plus 655 graphics and eDRAM.
What is the TDP of the i7-8559U?
It has a 28-watt TDP, higher than standard 15W U-series chips.
Does the i7-8559U have eDRAM?
Yes, it includes 128MB of eDRAM for its integrated graphics.
What Mac uses the i7-8559U?
It was used in the 2018 Mac Mini and the 13-inch MacBook Pro.
Can the i7-8559U be overclocked?
No, it is a locked processor.
What is the base clock of the i7-8559U?
It has a high base clock of 2.7 GHz.
Does the i7-8559U support DDR4?
Yes, it supports dual-channel DDR4 memory.
What graphics are in the i7-8559U?
It features Intel Iris Plus Graphics 655.
Is the i7-8559U better than the i7-8550U?
Yes, it has higher clocks and significantly better integrated graphics.
What generation is the i7-8559U?
It is an 8th Generation Intel Core processor.
Frequently Asked Questions
When was the Core i7-8559U released?
It was released on April 5th, 2018.
What is the max turbo frequency of the i7-8559U?
It can boost up to 4.5 GHz.
How much L3 cache does the i7-8559U have?
It has 8MB of L3 cache.
What socket does the i7-8559U use?
It uses the Intel BGA 1356 socket.
What memory speed does the i7-8559U support natively?
It natively supports DDR4-2400 memory.
Is the i7-8559U unlocked?
No, the multiplier is locked.
Does the i7-8559U support Quick Sync Video?
Yes, it supports Intel Quick Sync Video.
How many cores does the i7-8559U have?
It features 4 cores and 8 threads.
Does the i7-8559U support Windows 11?
Yes, it is officially supported by Windows 11.
What is the die size of the i7-8559U?
The die size is 123 mm².