What kind of processor do I need for Adobe Photoshop and Lightroom. A 2018 guide to CPU performance and photo editing.

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How To Guide

Cores and Threads

Most people think of the processor in your computer as its brain but I like to think of a modern processor being more like a factory.  You have data going in, some work being undertaken to that data in the processor via some calculations giving some output.  The faster it can undertake calculations, the faster your computer will feel to use and the faster it will be able to complete the set tasks.  Modern processors are divided into a number of processor cores.  One processor core is essentially like one factory production line.  By adding more cores, it is possible to undertake the same process in parallel many times over and get more output from your factory.  Processor cores are quite versatile, they can undertake entirely different tasks or they can all undertake a portion of the same task.

 

Some tasks are easy to divide out amongst many processor cores but other tasks are more difficult and only work with one processor core.  We refer to these tasks as being single threaded (only works on one core) or multi-threaded (works on many cores in parallel).

Processor clock speed explained

A processor Clock speed is usually measured in GHz (billions of pulses per second).  Each pulse represents the ability of the processor to perform an instruction or part of an instruction.  Usually, the faster the processor clock speed, the faster it will undertake a given task.  Photoshop performance scales directly with processor clock speed. Some processors also include a feature called Turbo Boost. This refers to Intel Turbo Boost Technology 2.0 which will try to increase the clock speed of the processors cores where safe to do so.

 

Intel® Turbo Boost Technology 2.0 accelerates processor performance for peak loads, automatically allowing processor cores to run faster than the rated operating frequency if they’re operating below power, current, and temperature specification limits. Whether the processor enters into Intel® Turbo Boost Technology 2.0 and the amount of time the processor spends in that state depends on the workload and operating environment.

 

To maximise performance under Turbo Boost, our Performance, High End, and Professional photography systems use a high performance CPU cooler. Regular CPU coolers won’t allow the CPU to operate under Turbo speeds for long before reaching maximum temperature.

Photoshop with multi core processors

If the computer is mainly used for Photoshop and Lightroom it is important to understand how efficiently these applications cope with multi core processors.  In order to understand this, we have undertaken testing using a range of processors from dual core right through to the huge 18 core variants.  We were quickly able to conclude that both Photoshop and Lightroom are not able to take advantage of a great number of processor cores.

 

There are some exceptions as certain effects will have a small benefit given additional cores.  On average however, we can conclude that it would be more beneficial to use a processor with fewer cores but higher processor frequency.  the performance of the processors scales in a linear fashion with increased processor frequency.

 

The best efficiency is gained from dual core or quad core processors.  We understand that most users will likely have other applications such as email, web browsers and various background tasks operating at the same time.  Moving to a 6 core processor will effectively give the use 2 spare cores to run other applications.  There seems to be little point moving above a 6 core product even for very high end Photography systems

We recomend 8th Generation 'K' SKU processors due to their high clock speed

Intel Core i3 8th Gen Badge
Intel Core i5 8th Gen Badge
8th-gen-intel-core-i7-badge-2-720x480-c

8th Generation Intel® Core™ i3 8350K Processor
Lithography 14 nm
Number of Cores 4
Number of Threads 4
Processor Base Frequency 4.0 GHz
Cache 8 MB SmartCache
Bus Speed 8 GT/s DMI3

8th Generation Intel® Core™ i5 8600K Processor
Lithography 14 nm
Number of Cores 6
Number of Threads 6
Processor Base Frequency 3.6 GHz
Max Turbo Frequency 4.3 GHz
Cache 9 MB SmartCache
Bus Speed 8 GT/s DMI3

8th Generation Intel® Core™ i7 8700K Processor
Lithography 14 nm
Number of Cores 6
Number of Threads 12
Processor Base Frequency 3.7 GHz
Max Turbo Frequency 4.7 GHz
Cache 12 MB SmartCache
Bus Speed 8 GT/s DMI3

A performance photography PC requires a processor able to handle the multitude of Photoshop actions and effects quickly and efficiently.  Photoshop can efficiently utilise multiple processor cores, but efficiency drops off after two cores, with the four-core processor only being around 25% faster than the two-core at the same clock speed.  The six-core processor is approximately 8% faster than a four-core.  There will be some variance depending upon the actual task being undertaken, but in general, there seems little point in upgrading beyond a six-core processor.

 

Performance in Photoshop does improve directly with increases in processor clock speed, the higher, the better.  It is, therefore, better to utilise a processor with fewer cores but a higher clock speed if budget is limited.  If you use the PC for a variety of tasks including video editing and image processing, you may still benefit from higher core counts from the other applications.

The below is a list of relative performance in an average of 10 common Photoshop effects and processes; benchmarked to the Core i5-7600 processor:

Intel Core i3-7100 3.9GHz Dual Core –>  75%

Intel Core i3-8100 3.6GHz Quad Core –> 95%

Intel Core i5-7600 3.5GHz / 4.1GHz Turbo, Quad Core –> 100%

Intel Core i3-8350K 4.0GHz Quad Core –> 105%

Intel Core i5-7600K 3.8GHz / 4.2GHz Turbo, Quad Core –> 106%

Intel Core i5-8400 2.8GHz / 4GHz Turbo, Six Core –> 106%

Intel Core i5-8600K 3.6GHz / 4.3GHz Turbo, Six Core –> 113%

Intel Core i7-7700K 4.2GHz / 4.5GHz Turbo, Quad Core, 8 Thread –> 117%

Intel Core i7-8700K 3.7GHz / 4.7GHz Turbo, Six Core –> 127%

Intel Core i7-7740X (overclock to 5.0GHz), Quad Core, 8 Thread –> 135%

Adobe Creative Cloud Photography Plan

Adobe Photoshop CC and Lightroom CC

Performance Photography Computer

SKU: 38701 - Built to order 7 - 10 days

£1,449.95 (inc VAT)

Intel Core Family 8th Generation *updated April 2018*

  • Be Quiet! Pure Base 600 Silent Tower Case
  • Intel Core i5-8600K 3.6/4.3GHz Six Core CPU
  • MSI Z370 PC PRO ATX Motherboard
  • NVidia GTX1050 Ti 4GB Graphics Card
  • 32GB (2x16GB) DDR4 2666Mhz Memory
  • 240GB ADATA SX8200 NVMe M.2 SSD
  • 480GB ADATA SX8200 NVMe M.2 SSD
  • 4TB Seagate BarraCuda 3.5″ Hard Drive
  • Raijintek Aidos CPU Cooler
  • 500W Power Supply
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  • 2 x USB 3.0 at the front
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  • 2 x USB 3.1 Gen2 (1xType-C + 1xType-A) at the back
  • Supports up to 3 monitors
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