MacBook Air (mid 2013, 13", i5) - Geekbench scores on MacOS and Ubuntu Today I decided to do a clean install on MacBook Air - did an online recovery, erased the disk and installed MacOS High Sierra. Even clean it didn't behave really good so I decided to try Geekbench - with the Mac restarted and only the Geekbench app running - I got pretty low score -  1251 on single core and 2457 on multiple cores. 



By a chance I had a Kali Linux (Debian) Live USB nearby so I decided to boot it and try Geekbench again. Got about three times better scores on both. 

Got really suspicious and decided to wipe the Mac again and installed Ubuntu 17.10 to try the test again and it got an even better score -  - 3294 on single core and 5773 on multiple cores. 


It just feels much better - runs smoother, everything feels faster... 
Why could that be? I'm super confused. Can anyone shed some light on my case?
Why would that be?

Any number of reasons; however I would point towards testing methodology.  Looking at the Geekbench Score for a MacBook Air 11" Mid 2013, it got double your posted score and fairly in line with Ubuntu.

It's important to note that the score on the following chart are the "average" scores - meaning many higher and lower.


  To make sure the results accurately reflect the average performance of
  each Mac, the chart only includes Macs with at least five unique
  results in the Geekbench Browser.




Why the large variance?


macOS High Sierra, you didn't specify if you were using the latest updated version. 
One test was done with a live CD
The Ubuntu score is referenced directly (unlike the others).  What "tuning" was done, if any is not noted.
macOS will limit the amount of CPU available to manage temperature.  Ubuntu does not.


Those are just some of the possible reasons for the large variance and is by no means an exhaustive list.