Best OS for iMac 2015

Question

Level 1

7 points

Best OS for iMac 2015

Which is the better performing OS for an iMac 21.5 Late 2015?

It originally came with OS Sierra but was 'upgraded' to OS Catalina 10.15.5 by the previous owner. It seems to be running a bit slow and I'm wondering if this is the best OS for this iMac? Any input will be appreciated.

It has:

Hardware Overview:

Model Name: iMac

Model Identifier: iMac16,2

Processor Name: Quad-Core Intel Core i5

Processor Speed: 2.8 GHz

Number of Processors: 1

Total Number of Cores: 4

L2 Cache (per Core): 256 KB

L3 Cache: 4 MB

Memory: 8 GB

Graphics: Intel Iris Pro Graphics 6200 1536 MB

Boot ROM Version: 476.0.0.0.0

SMC Version (system): 2.32f21

Thank you

Sara S.

[Personal Information Edited by Moderator]

Posted on Jan 18, 2023 11:14 PM

Reply

Answer 1

Top-ranking reply

Jack-19

Level 8

46,182 points

Jan 18, 2023 11:53 PM in response to saras0821

Hello!

The best version of macOS for your iMac is macOS Monterey. However, the reason your iMac is slow is due to the 5400-rpm hard drive. While this hard drive found in your Mac is perfectly suited to light tasks, such as email, web browsing, etc., for more advanced tasks, and for users who want the maximum performance from their Mac, this hard drive does have its limitations. Luckily, you can use an external SSD as your startup disk to run macOS and all your data from that. It will make your Mac 10 to 40 times faster for storage, and in turn, make your entire Mac system much faster. For more info, instructions, and what external SSD to buy, please see: How to Setup and Use an External SSD as your Startup Disk on a Desktop Mac - Apple Community.

Jack

Reply

Answer 2

hcsitas

Level 6

13,964 points

Jan 18, 2023 11:58 PM in response to saras0821

In that case, no additional action necessary. Be sure it doesn’t have any dubious software involved like anti-virus, malware etc.

Reply

Answer 3

hcsitas

Level 6

13,964 points

Jan 18, 2023 11:22 PM in response to saras0821

Yes it is. The slowdown is probably due to the hard disk, especially if it’s fusion. Graphics is outdated too. Hang in there before replacing, M2 iMac is likely around corner.

Reply

Answer 4

saras0821 Author

Level 1

7 points

Jan 18, 2023 11:40 PM in response to saras0821

FYI.....

The hard drive is:

2.8GHz

1TB (5400-rpm) hard drive

(Configurable up to 2TB Fusion Drive or 256GB of flash storage (SSD))

I am setting this iMac up for a friend and I am a little unfamiliar with the best OS choice for this model iMac. My friend is not at all interested in updating to newer models as she just needs it for very basic use & internet access.

Thanks for any advice on best OS.

Sara

Reply