If Photoshop feels sluggish, the problem usually isn’t your computer — it’s how Photoshop is configured. The default settings are conservative, designed to work on low-end hardware. If you have a decent machine, you’re leaving performance on the table.
Here’s how to configure Photoshop for speed.
Memory (RAM) Allocation
Go to Edit > Preferences > Performance (Photoshop > Settings > Performance on Mac).
The “Memory Usage” slider controls how much RAM Photoshop can use. The default is around 70%.
Set it to 80-85%. If Photoshop is the only heavy application you run, you can push to 85%. If you regularly have Lightroom, a browser, and Photoshop open simultaneously, stay at 75-80%.
Going above 85% can cause system instability because your operating system and other processes need RAM too.
Scratch Disks
Scratch disks are where Photoshop stores temporary data when it runs out of RAM. By default, this is your system drive.
Optimal setup:
- If you have an SSD (you should), your system drive is fine as the primary scratch disk
- If you have a second SSD, add it as an additional scratch disk
- Never use an external USB drive as a scratch disk — the bandwidth is too low
- If you’re on a spinning hard drive, consider an SSD upgrade before any other optimization
How much space? Keep at least 50-100GB free on your scratch disk. Large panoramas and files with dozens of layers can consume enormous amounts of scratch space.
GPU Settings
Under the same Performance panel, make sure “Use Graphics Processor” is checked and set to “Advanced” in the drop-down.
GPU acceleration affects:
- Zooming and panning smoothness
- Brush rendering speed
- Filter previews
- 3D features (if you use them)
If you experience display glitches (flickering, rendering artifacts), try setting this to “Basic” instead. Some GPU drivers have compatibility issues with Advanced mode.
History States
The default is 50 history states. Each state consumes memory proportional to the changes made.
Set it to 20-30 if you’re working with large files. You rarely need to undo more than 20 steps, and the memory savings are significant. If you need more undo flexibility, use snapshots instead — they’re more memory-efficient for saving specific states.
Cache Levels and Tile Size
Cache Levels: Controls how many downsampled versions of your image Photoshop maintains for faster screen rendering.
- Working with large files (50+ megapixels): Set to 6-8
- Working with small files or web graphics: Set to 2-4
Cache Tile Size:
- “Tall and Thin” (128K) for smaller files with many layers
- “Big and Flat” (1024K) for large single-layer or few-layer files
If you’re not sure, the “Default” preset is reasonable.
File Handling
Under Edit > Preferences > File Handling:
- Disable “Always Save Preview” if you don’t need JPEG thumbnails in your PSDs. This speeds up saves noticeably on large files.
- Set “Maximize PSD File Compatibility” to “Ask” rather than “Always.” The compatibility feature roughly doubles your PSD file size.
Quick Wins
A few more settings that make a noticeable difference:
- Disable animated zoom: Preferences > Tools > uncheck “Animated Zoom.” This eliminates the smooth zoom animation that can feel laggy on large files.
- Rich tooltips: Preferences > Tools > uncheck “Show Rich Tooltips.” These are the animated popup explanations that appear when you hover over tools. They consume resources for no benefit once you know the interface.
- Font preview: Preferences > Type > reduce or disable font preview size. Large font previews slow down the font menu considerably if you have hundreds of fonts installed.
The Nuclear Option
If Photoshop is still slow after optimization, reset preferences entirely. Quit Photoshop, then hold Ctrl+Alt+Shift (Cmd+Option+Shift on Mac) while launching it. Click “Yes” to delete the preferences file. This resets everything to defaults and clears any corrupt settings that might be causing issues.
You’ll need to reconfigure your preferences, but it resolves a surprising number of mysterious performance problems.