Three primary factors dictate how well Photoshop CS5 runs on your computer: system RAM, CPU speed, and GPU capability. In addition, the way you configure your application also plays a major part. For a better overall performance, you must make a hardware upgrade, but since that is not always possible this short guide concentrates on configuration. You'll learn about optimizing performance and getting the most out of your current hardware.
Get 64-bit Photoshop & 64-bit OS
Though many would expect a 64-bit Photoshop run on a 64-bit OS to show a significant performance boost compared to a 32-bit one run on a 64-bit OS, this isn't the case. The increase in operation speed is about 15% at most. Still, it's a noticeable improvement, and it will especially show when you work with large files. What's more, a 64-bit Photoshop on a 64-bit OS means that you can allocate more than 3.2Gb RAM to CS5 (see next rule for more on allocating RAM).
Allocate More RAM
When it comes to allocating RAM there's no a set value that works for everyone. It all depends on your machine and on the type of files which you most frequently work with. Moreover, it also depends on how many background programs you like to run at the same time. In order to make the most of your available RAM you have to experiment.
Go to Edit>Preferences>Performance and play with the memory slider. The default should be 60%. Now if you run 64-bit Photoshop on a 64-bit OS you won't have any limitations: you can use all the memory available, except of course that required by the OS. Setting the slider to 65% or 70% should normally increase the CS5 performance and still let you run plenty applications in the background, such as a web browser, music player, antivirus etc.
As a last resort, when you don't have enough RAM installed, you must start closing background apps. Start with the least important. It's wise to keep the antivirus on, otherwise you may miss important security updates. Usually, if you close all other extra background programs you'll be able to allocate as much as 90% to 95% of available memory to CS5 (OS allocated memory excluded).
Note: Disable Adobe Bridge if you don't really use it. Make sure it doesn't launch automatically when Photoshop does.
Adjust Cache
Image caching is used in Photoshop for the real-time update of a low-res version of an image just as you work on it. Go to Edit>Preferences>Performance and look for the Cache option. It has eight levels, from 1 to 8, and the default is 4. To disable this feature and cache only the image you edit choose 1. When the setting is 4 or more the performance increases for larger images. Your final choice depends on what sort of images you work with. It would be wise if you adjust this setting each time you start working on a large project.
GPU vs. CPU: Buy GPU
Though a good CPU means a quicker Photoshop, the effect of the CPU's speed on performance is not that great. By contrast, RAM is much more important. A top GPU on the other hand, can dramatically boost the speed at which screen redraw is done, provided of course that you set the Photoshop CS5 to use the GPU instead of the CPU for this. This is why if you consider a hardware upgrade and already have a good processor your money will be best invested in a top GPU.
