Several months after the launch of the Nehalem microarchitecture (and the Intel Core i3, i5 and i7 processors, based on that architecture), all logos for Intel processors were updated (by FutureBrand), including the logos for the previous-generation Intel Core 2 CPUs.
In 2011, Intel unveiled new logos for the "second-generation Intel Core processors", based on the Sandy Bridge microarchitecture (and these logos are also used for the Intel Core chips based on the Ivy Bridge microarchitecture, a.k.a. the "third-generation Intel Core processors"). Nehalem-based Intel Core CPUs remained with the 2009 logos.
In 2013, with the launch of the "fourth-generation Intel Core processors", based on the Haswell microachitecture, new logos for this generation of CPUs were introduced. Sandy Bridge- and Ivy Bridge-based chips remain with the 2011 logos.
Some PCs with Haswell on them may have the Broadwell sticker on them.
In 2015, with the launch of the "sixth-generation Intel Core processors", based on the Skylake microachitecture, new logos for this generation of CPUs were introduced. Haswell- and Broadwell-based chips remain with the 2013 logos.
These logos are used on pre-built systems featuring both Intel Core processors and Intel Optane memory.
Skylake, Kaby Lake and Coffee Lake-based chips remain with the 2015 logos.