April 3, 2015
For the most part, you’ll get faster CPU performance from Core i7 than Core i5. The majority of Core i7 desktop CPUs are quad-core processors, but so are the majority of Core i5 desktop CPUs. This is not always the case, as there are dual-core mobile Core i7 processors and many dual-core mobile Core i5 CPUs. You might also see the rare six- or eight-core Core i7, but that’s usually found with the desktop-only, top-of-the-line Extreme Edition models.
The Core nomenclature has been used for several generations of CPUs. Nehalem and Westmere use three-digit model names (i.e., Intel Core i7-920), while Sandy Bridge, Ivy Bridge, Haswell, and Broadwell CPUs use four-digit model names (such as the Intel Core i7-5500). Thankfully, unless you’re shopping the used PC market, you’ll find Ivy Bridge processors in closeout systems and budget PCs, while you’ll find Haswell or Broadwell processors in most new PCs. Older-generation Nehalem, Westmere, and Sandy Bridge cores are found in older PCs and generally have lower performance. The essential takeaway is that to get better performance in each generation, buy a processor with a higher model number. For instance, an Intel Core i7-5500U generally has better performance than an Intel Core i5-5200U.
Give Me the Cache
In addition to generally faster base clock speeds, Core i7 processors have larger cache (on-board memory) to help the processor deal with repetitive tasks faster. If you’re editing and calculating spreadsheets, your CPU shouldn’t have to reload the framework where the numbers sit. This info will sit in the cache, so when you change a number, the calculations are almost instantaneous. Larger cache sizes help with multitasking as well, since background tasks will be ready for when you switch focus to another window. On currently available desktop processors, i5 CPUs have 3MB to 6MB of L3 cache, while i7 processors have 4MB to 8MB. Read more of this post