The short answer is no.
The long answer. There are two primary vectors to discuss.
- Applications that execute on a single thread.
- Applications that execute on two or more (many) threads.
1. Single Threaded
An application that can only take advantage of one virtual core (or thread) is known to be single threaded. There are several reasons for this:
- There is no reason to add support for additional threads. It would just add needless complexity.
- The program is poorly written.
- The problem it is trying to solve is linear and will not benefit from additional threads.
Most of your applications will consume less than one core's worth of performance at any time. Having multiple cores allows you to run multiple single-threaded programs at once without suffering any slowdown. Many of the more basic programs you use everyday will be single threaded, and it should almost never become an issue.
In order to increase the performance, one must change the microarchitecture, or increase the clock speed. Intel has decided to use a technology called
Turbo Boost to increase the clock speed of the processor based on the thermal overhead and/or number of cores active. This existed with mobile Westmere (Arrandale), but it was unreliable and would not step up bins as often as one would hope. With Sandy Bridge, Intel made Turbo Boost much more consistent and reliable. Most of the single-threaded performance difference between Ivy Bridge and Sandy Bridge is that Ivy Bridge boosts higher more often.
2. Multi Threaded
This kind of application can take advantage of however many cores it was programmed to. Raytracers and radiosity solvers such as Mental Ray can take advantage of as many cores as it has available. Other programs like Photoshop, Handbrake, and Starcraft 2 have a limited amount of parallelisation they can perform. Starcraft 2 is infamously limited to two threads, whereas Handbrake seems to run into a limitation in the encoder and maxes around six threads (at least last I used it). Certain parts of Photoshop CS5 and CS6 are well threaded, other parts are often very poorly threaded.
It is worth looking into the programs you use and figuring out which are most intensive. If you are primarily running a stressful single-threaded program, a case can easily be made for the faster CPU. If your workloads are more multi-threaded, the difference between CPUs shrinks.
Analysis
I have attached to this post three charts which rank several Intel processors.
Cinebench R10 Singlethreaded shows the single threaded performance as measure in Cinebench R10 rendering on only one core. The 2.3GHz current-gen chip is roughly keeping pace with the highest performance SBN chip from last generation. Delta is about 8% vs the high end IVB. This is worst case scenario, there just aren't enough brute force cycles to keep up.
Cinebench R11 Multithreaded shows the multi-threaded performance as measured in Cinebench R11. The renderer in R11 is substantially improved over R10, and is more representative of the actual performance. As we can see the low-end IVB outpaces the previous highest BTO SBN considerably. The difference between all three IVB chips is fairly small. About 4% for 3615 vs 3720.
Geekbench Scores paints a more general picture. Geekbench is useful for comparing machines from more of a general synthetic performance standpoint. The low end IVB is the equal of high-end SBN from last gen. Anybody who has a top-of-the-line 2011 SBN MBP can tell you it is wicked fast.
Processor Legend:
- i7-3770K - This is a current generation Ivy Bridge desktop part rated at 77 watts. Having this included helps illustrate exactly how close mobile parts are getting to desktop parts these days.
- i7-3820QM - The 2.7GHz BTO high end part you can spec in the top model MacBook Pros today. This is an Ivy Bridge part, and has 100MHz increased frequency, and 2MB additional cache over the standard high-end part.
- i7-3720QM - Standard 2.6GHz high-end part in both Retina and non-Retina mid-2012 MBP.
- i7-3615QM - A slightly slower part, 2.3GHz low-end MBP Ivy Bridge part from this generation.
- i7-2860QM - The BTO high end Sandy Bridge part from last generation MacBook Pros. This has 8MB of L3 as well.
- i7-2760QM - High-end Sandy Bridge part for last generation MacBook Pros.
- i5-520M - Much slower SKU from mobile Westmere. This was in the low end 15" MBP from 2010. It helps frame the bottom of the chart, and illustrates how far we've come since 2010. As well as how much of a performance improvement SBN was.
NOTE: All of my data here was taken from aggregate internet sources and charted myself in Numbers. It is meant only as a general guide and could have inaccuracy. However, all sanity checks I've performed show that it is quite representative of real-world performance.