Intel Core i5-3550
Another lowering of the model number once again indicates that the computing power will get lower, too. In this case Core i5-3550 is slower than Core i5-3570 because of slightly lower clock speed. However, the difference is only around 100 MHz or 3%, so it is not surprising that Intel priced Core i5-3570 and Core i5-3550 similarly. They anticipate the Core i5-3570 to slowly oust Core i5-3550 from the stores. That is why all other specifications of these two processors, except the clock frequency, are identical.
Intel Core i5-3470
The MSRP of the two junior Core i5 processors on the 22 nm Ivy Bridge core is set below $200. They are currently retailing at around this price point. However, Core i5-3470 is not that much inferior to the top Core i5 processors: it has all four computational cores, 6 MB L3 cache and over 3 GHz clock frequency. Intel decided to use a 100 MHz increment to differentiate between the modifications in the refreshed Core i5 lineup, therefore, you can hardly expect different processor models to demonstrate dramatically different performance in real applications.
However, Core i5-3470 has different graphics performance than the top processors in the family. HD Graphics 2500 core in this processor works at a slightly lower clock speed: 1.1 GHz vs. 1.15 GHz by the more expensive CPU models.
Intel Core i5-3450
The very junior 3rd generation Core i5 processor, Core i5-3450, slowly leaves the market, just like Core i5-3550. Core i5-3450 is being replaced by the above described Core i5-3470, which works at a slightly higher clock frequency. There are no other differences between these processors.