Slow iMac running macOS Ventura performance after reinstall

My partner's iMac (2017/Ventura) runs very very slowly. I went through all the usual problem solving options and finally saved her files and did a full reinstall. Having replaced her files the machine initially ran at proper speed but, over the course of a few days, slowed right down again. I suspect a corrupted file but - out of the thousands on the HD - how do I find it?

[Re-Titled by Moderator]

Original Title: Very slow imac

iMac Pro (2017)

Posted on Jul 8, 2025 2:53 AM

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101,983 points

Posted on Jul 8, 2025 4:57 AM

There are 3 different iMacs from 2017

To avoid a session of Q&A, Q&A and Q&A

Download the Application Etrecheck ( External Link ) directly from the Developer.

This is a Diagnostic Tool that makes no changes to the computer.

It makes a coherent and readable inventory of both the Hardware and Software used on the computer

The application is free or paid for added features.

The Report will Not Reveal Any Personal Information.

Post back the Full Report - Share Report >> Copy , then paste >>>> using the Additional Text Icon <<<<

Lastly - should you decide to use and post the Report now or at a later time, we are willing to have a very close look and offer some insights

1 - iMac (21.5-inch, 2017) - Technical Specifications

2 - iMac (Retina 4K, 21.5-inch, 2017) Manuals

3 - iMac (Retina 5K, 27-inch, 2017) Manuals

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1 reply

Top-ranking reply

Level 10

101,983 points

Jul 8, 2025 4:57 AM in response to stuartcornwall

There are 3 different iMacs from 2017

To avoid a session of Q&A, Q&A and Q&A

Download the Application Etrecheck ( External Link ) directly from the Developer.

This is a Diagnostic Tool that makes no changes to the computer.

It makes a coherent and readable inventory of both the Hardware and Software used on the computer

The application is free or paid for added features.

The Report will Not Reveal Any Personal Information.

Post back the Full Report - Share Report >> Copy , then paste >>>> using the Additional Text Icon <<<<

Lastly - should you decide to use and post the Report now or at a later time, we are willing to have a very close look and offer some insights

1 - iMac (21.5-inch, 2017) - Technical Specifications

2 - iMac (Retina 4K, 21.5-inch, 2017) Manuals

3 - iMac (Retina 5K, 27-inch, 2017) Manuals

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Slow iMac running macOS Ventura performance after reinstall

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