PCH - The Platform Controller Hub Chipsets
PCIe lanes
With PCIe Gen 3.0. Haswell processors and platforms can feature 16 PCIe 3.0 lanes to be used for graphics and/or other add-in PCI cards. All desktop chipsets have a single PCIe x16 device, the two Z8x chipsets add the option to use two devices at x8. The inclusion of PCI Express Gen 3 is great, but what does that boil down to? Well, simply put, PCI Express Gen 3 provides a 2X faster transfer rate than the previous generation, this delivers capabilities for next generation extreme gaming solutions. PCI Express Gen 3 has twice the available bandwidth, 32GB/s, improved efficiency and compatibility and as such it will offer better performance for current and next gen PCI Express cards. Going from PCIe Gen 2 to Gen 3 doubles the bandwidth available to the add-on cards installed, from 500MB/s per lane to 1GB/s per lane. So a Gen 3 PCI Express x16 slot is capable of offering 16GB/s (or 128Gbit/s) of bandwidth in each direction. That results in 32GB/sec bi-directional bandwidth. Obviously the hardware you use needs to be compatible.
USB 3.0
It should be abundantly clear by now but USB 3.0 is supported at chipset level by Intel, which should save motherboard vendors money when building Intel chipset based boards and hopefully making them overall less complicated to design. In addition to that, we will hopefully see better USB 3.0 performance. The chipset will now host six USB 3.0 ports. Next to that 14 USB 2.0 ports are supported from the PCH. It is up-to the chipset type and motherboard manufacturers how many will be implemented of course.
LGA 1150 - A new Socket
With Sandy Bridge we moved to socket LGA 1155, for Ivy Bridge we kept that socket. Haswell however will require a new socket, LGA 1150. The bad news is that you'll be required to purchase a new motherboard. The good news is that the cooler pins are similar to 1155/1156 so you can re-use your cooler. So, you do not need to purchase a new CPU cooler. You'll be amazed by the sheer amount of motherboards released in the upcoming weeks.