Skylake isn't just about the CPU, either. It's a whole platform. The move to DDR4, and the much-improved Z170, makes it the natural replacement for anyone considering building or buying a high-end, mainstream PC.
What I'd do if:
I had a quad-core Haswell
If you have a Haswell-based system, skip this upgrade. It just doesn't make sense, and Intel probably doesn't even expect you to upgrade.
If you have a quad-core Sandy Bridge or Ivy Bridge PC
I'd seriously look at this upgrade. Skylake is clearly faster than Sandy Bridge and Ivy Bridge, but it's not a night-and-day situation. What is night-and-day is the chipset. The chipsets made for the 2nd- and 3rd-gen CPUs are simply ancient. People forget, but they don't support USB 3.0 natively, and SATA 6Gbps is available on only two of the six ports. For you, it's a not a bad upgrade to move into a modern CPU and chipset.
If I had a Core 2 Quad
I'd wait for Intel's Skylake refresh, called Kaby Lake. Is that because it'll be better and faster? No, If you're still sitting with a Core 2 Quad from circa 2007, you're probably the kind of person who's always going to wait for the next big thing. So you'll wait for Kaby Lake in 2016, and once that's out, you'll wait for Cannonlake in 2017. In other words, I'm kidding. If I had a Core 2 Quad and was waiting for "the right time" to upgrade, this is a good one.
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