I'll focus on the Geekbench 3 score, because it is the most widely used, and in particular on its single-core, 64-bit score, as I think this is the number that best reflects the experience I have using the computer as a developer. Let's look at two other lines that made the move to Haswell processors over the last year:
- The iMac, from late 2012 (3542) to late 2013 (3935), saw an 11% improvement.
- The MacBook Air, from mid-2012 (2863) to mid-2013 (3143), saw a 10% improvement.
I'll predicate my prediction on the MacBook Pro Retina seeing a similar relative improvement. The MacBook Pro Retina from early 2013 scored 3395, so I predict the new "late 2013" MacBook Pro Retina will score at about 3393*1.1 = 3732.
This would make the iMac only just over 5% faster than the MacBook Pro Retina, which would make it hard to for me to choose between the latest MacBook Pro Retina and latest iMac.
Update (2013-10-22): The most high-end CPU we can get on the MacBook Pro like is described as a 2.6GHz Quad-core Intel Core i7 with Turbo Boost up to 3.8GHz, which according to Wikipedia is a i7-4960HQ with 6 MB on-chip L3 cache. The high-end late-2013 iMac comes with a i7-4771, still according to Wikipedia. Based on the specs, the iMac CPU more cache (8 MB vs. 6 MB) but the memory bandwidth MacBook Pro CPU is higher (76.8 GB/s vs. 25.6 GB/s). However, at this point we don't yet have published performance scores for the i7-4960HQ on Geekbench.
Update (2013-10-23): CPU World has a useful comparison of the MacBook Pro's i7-4960HQ (left) with the iMac's i7-4771 (right). Of interest, this comparison mentioned the F16C additional instructions of the iMac's i7-4771, which provide support for doing half-precision to and from single-precision floating-point conversions, but it isn't clear that the availability of those instructions would improve the performance of tasks typically performed by developers.
Also, a few 32-bit scores for the i7-4960HQ started showing up. There are too few to draw any conclusion, and we'd like to look at 64-bit scores, but taking a value of 3405 for the 32-bit MacBook Pro's i7-4960HQ scores and of 3584 for the 32-bit i7-4771 scores, the iMac would indeed be just 5% faster.
Update (2013-10-22): The most high-end CPU we can get on the MacBook Pro like is described as a 2.6GHz Quad-core Intel Core i7 with Turbo Boost up to 3.8GHz, which according to Wikipedia is a i7-4960HQ with 6 MB on-chip L3 cache. The high-end late-2013 iMac comes with a i7-4771, still according to Wikipedia. Based on the specs, the iMac CPU more cache (8 MB vs. 6 MB) but the memory bandwidth MacBook Pro CPU is higher (76.8 GB/s vs. 25.6 GB/s). However, at this point we don't yet have published performance scores for the i7-4960HQ on Geekbench.
Update (2013-10-23): CPU World has a useful comparison of the MacBook Pro's i7-4960HQ (left) with the iMac's i7-4771 (right). Of interest, this comparison mentioned the F16C additional instructions of the iMac's i7-4771, which provide support for doing half-precision to and from single-precision floating-point conversions, but it isn't clear that the availability of those instructions would improve the performance of tasks typically performed by developers.
Also, a few 32-bit scores for the i7-4960HQ started showing up. There are too few to draw any conclusion, and we'd like to look at 64-bit scores, but taking a value of 3405 for the 32-bit MacBook Pro's i7-4960HQ scores and of 3584 for the 32-bit i7-4771 scores, the iMac would indeed be just 5% faster.
