Scratch Disks for Adobe

Improve Computer Performance

When your system does not have enough RAM to perform an operation, several Adobe applications use a proprietary virtual memory technology, also called scratch disks. A scratch disk is any drive or drive partition with free memory. By default, Photoshop, Illustrator, and After Effects use the hard drive on which the operating system is installed as the primary scratch disk. 

The following guidelines can help you assign scratch disks: 

For best performance, scratch disks should be on a local drive. That is, they should not be accessed over a network. Scratch disks should be conventional (non-removable) media. So, no external hard drives.

Your primary scratch disk should be your fastest hard disk; make sure it has plenty of defragmented space available.

Assigning scratch disks in Photoshop

1. Open Photoshop
2. Select Photoshop > Preferences > Scratch Disks
3. Set the Scratch Disk:
4. On an MCAD Student MacBook: Check the box next to Macintosh HD. With this drive selected, click the up-arrow key to set it as the number 1 Scratch Disk. Click OK to close the window.

Assigning scratch disks in Illustrator

1. Open Illustrator
2. Select Illustrator > Preferences > Plug-ins & Scratch Disks
3. Set the Scratch Disk:
4. On an MCAD Student MacBook: set the Primary scratch disk to Startup. Set Secondary to None.
5. Click OK to close the window.

Assigning scratch disks in After Effects

1. Open After Effects
2. Select After Effects > Preferences > Media & Disk Cache
3. Turn on Enable Disk Cache
4. On an MCAD Student MacBook: Select a folder within the Macintosh HD and click the Choose button
5. Under Maximum Disk Cache Size: set to between 500 and 2000MB depending on the amount of free space on the scratch disk drive. 

If you run into issues with Scratch Disks, please contact the MCAD Help Desk by emailing helpdesk@mcad.edu or by phone at 612-874-3666.