Speed Difference between intel i7 and i5 under MacOS

As I've mentioned before, my old iMac was broken, but I managed to fix it.  In the intervening time, I bought one of the core retina iMacs instead.  Since this was an i5, I decided to benchmark it on some video transcoding that I do a lot of to see the difference between the machines in general.  e.g. # cores, speed, cache etc.  I also ran the comparison on my MacBook Pro as well. All machines have a native SSD and are running the latest build of High Sierra.

Machine information:

New:

• iMac Retina 5K 2-inch 2017
• Processor 3.5GHz Intel Core i5 (4 cores)

Old:

• iMac 27-inch Later 2009
• Processor 2.8GHz Intel Core i7 (8 cores)

Laptop:

• Macbook Pro 15-inch Late 2016 (Touch Bar)
• Processor 2.7GHz Intel Core i7 (8 Cores)

Details of test:

• Nightly build of HandBrakeCLI from 2018-02-10
• Uses all available cores if possible, as it's multi-threaded.  A good test of multiple cores.
• Mp4 file of 1920x1080 resized to 960x270 using Quality of 22.

Old	New	Laptop
14m 41s	10m 16s	13m 26s

Notes:

• New encoding details:

x264 [info]: using SAR=1/1

x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2

x264 [info]: profile Main, level 4.0

• Old encoding details:

x264 [info]: using SAR=1/1

x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2

x264 [info]: profile Main, level 4.0

• Laptop encoding details:

x264 [info]: using SAR=1/1

x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2

x264 [info]: profile Main, level 4.0

Conclusion:

1. The new iMac running at a higher clock speed but with fewer cores is definitely faster than the 9 year old.
2. The 9 year old iMac still does surprisingly well.
3. The laptop, even though clocked at around the same speed and with 8 cores, is still slower than the desktop.