FSB QPI

LGA775 platform uses FSB, X58 uses QPI. QPI is a lot faster than FSB and it's used by Core i7 9xx CPU's. Core 2 CPU's use FSB, i3,i5 and i7 8xx use DMI, which is between FSB and QPI in speed.

A Front Side Bus is a large parallel subsystem that transfers data between computer components inside a computer or between computers. Every component on a motherboard is connected to, and therefore shares, a single Front Side Bus (there are systems with parallel FSBs but that's another issue entirely).

QPi, or Quick Path Interconnect, is a Point to Point Interconnect. It connects the CPU (or several CPUs) to a I/O HUB (In and Out Hellenic United Backbone). The I/O HUB is where the devices on the motherboard connect too. A single Point connecting various devices to one or more Point to Point interconnects. QPi works in a serial-differential manner (as opposed to the parallel manner in which FSB works).

QPi therefore offers the ability to transfer larger amounts of data on a smaller electrical footprint than a Front Side Bus. The signal integrity is also less prone to degrading in a Point to Point Interconnect than it is with a Front Side Bus when scaling the operating frequency in an upwards fashion.

QPi offers:
1. Lower Latencies
2. More Bandwidth
3. More Scalability
4. Lower Footprint
5. Cheaper Implementation

ok lets skip to the good stuff
QPI is the link of the components like cpu + ram + gpu if it was higher its better my rig QPI is 4.8 GT/s before my building i was looking for 8's of i7 and its QBI is 2.5 GT/s and thats why i got my 9's of i7