Although the Xeon includes added cache, it maintains the aforementioned one-core-to-2.5 MB adjustment as the Amount i7, and absolutely best of the added Xeon E5 models.
The added notable aberration amid single-socket Amount i7s/Xeon E5-1600s and Intel’s multi-socket platforms is the acknowledgment of QPI. When Intel replaced the Gulftown-based processors with Sandy Bridge-E, it accompanying confused from three-piece platforms (CPU, northbridge, and southbridge) to a two-chip blueprint (CPU, belvedere ambassador hub), eliminating the I/O hub amenable for hosting PCI Express connectivity. The articulation amid processor and northbridge, ahead facilitated by QPI, was severed. With PCIe congenital appropriate into Sandy Bridge-E, the southbridge basic could be anchored appropriate up to the CPU through a PCI Express-like Direct Media Interface. Thus, QPI is absolutely abeyant on Sandy Bridge-E.
Multi-socket systems still charge it for inter-processor communication, though. Sandy Bridge-EP CPUs affection two QPI links. In 2S configurations, they’re both acclimated to shuttle abstracts aback and alternating amid sockets. With four processors in play, they actualize added of a circle, abutting anniversary dent to the appropriate and left. Intel tinkers with the QPI abstracts amount as a appropriate feature, but admitting the Xeon 5600s topped out at 6.4 GT/s, acquiescent 25.6 GB/s per link, the highest-end Xeon E5s host 8 GT/s links, blame bandwidth to 32 GB/s per link. Obviously, in a 2S workstation like ours, 64 GB/s of accumulated QPI bandwidth is super-duper overkill. But we’re blessed to apperceive that the canicule of front-side bus-based bottlenecks are over.
Aside from amount count, last-level cache, and QPI, Sandy Bridge-EP is architecturally agnate to Sandy Bridge-E. AVX support, AES-NI, second-gen Turbo Boost, Hyper-Threading—all of those accustomed capabilities are included.
The alone added aberration of agenda is that Sandy Bridge-EP’s quad-channel anamnesis ambassador supports mirroring, distinct accessory abstracts correction, and lockstep. All three were accessible from Xeon 5500/5600 as well, but the accomplished triple-channel anamnesis ambassador adjustment apprenticed compromises. Now, you can mirror two channels and balance from a abortion in each. Hooray for nice, annular numbers.