Can't enable GPU Preview from CPU, Illustrator very slow.

[MrsShannon]

Illustrator CC 2021, GPU Performance switched on in preferences, yet when I open a document (new or existing) it's in CPU Preview. I tried to enable GPU Preview from the drop down 'View' menu is Illustrator but it won't let me change it. It's making working really slow and tedious, any suggestions please? 

[sishamIAGD]

Can you post a screenshot of your Preferences>Performance screen please..?

You may need to uninstall and reinstall or reset preferences...?

Windows user: Press and hold Alt+Control+Shift as you start Illustrator.
Mac OS user: Option+Command+Shift as you start Illustrator.

[Ashutosh_Mishra]

Hi there,

Sorry to hear about your experience. In addition to the suggestion given earlier, please try steps shared on this community post(https://community.adobe.com/t5/illustrator/resolve-slow-performance-and-unexpected-behaviors-in-illu...) & let us know if they help.

Regards,

Ashutosh