Three Generations Of Xeon E3-1275 CPUs
Intel maintained processor interface compatibility between the Sandy and Ivy Bridge-based Xeon E3s, both of which dropped into LGA 1155 sockets. In most cases, upgrading from one to the other was achievable through a firmware update. With the introduction of Haswell, notable changes (such as the fully-integrated voltage regulator) necessitate a new interface called LGA 1150, which naturally requires updated motherboards and platforms.
| Processor | Architecture | Manufacturing Process | Interface | Introduced |
|---|---|---|---|---|
| Intel Xeon E3-1200 | Sandy Bridge | 32 nm | LGA 1155 | 2011 |
| Intel Xeon E3-1200 v2 | Ivy Bridge | 22 nm | LGA 1155 | 2012 |
| Intel Xeon E3-1200 v3 | Haswell | 22 nm | LGA 1150 | 2013 |
In addition to the interface change that happened between Ivy Bridge and Haswell, Intel also transitioned to 22 nm manufacturing between Sandy and Ivy Bridge, true to its tick-tock cadence. The primary beneficiary of this technology advancement was the mobile segment. But because Intel's Xeon E3-1200 series leverages the same architectures as Intel's Core i3, i5, and i7 CPUs, those mobility-oriented enhancements (primarily affecting power) make their way into the Xeon line-up, too.
Up until recently, the Xeon E5s were all based on the older 32 nm Sandy Bridge-EP/EN architecture. Intel introduced its v2 family at IDF earlier in the month. But the company is still one generation behind in the Xeon E5 series compared to these Haswell-based E3s.
In terms of specifications, the following table compares all three generations:
| Header Cell - Column 0 | Xeon E3-1275 | Xeon E3-1275 v2 | Xeon E3-1275 v3 |
|---|---|---|---|
| # of Cores | 4 | ||
| # of Threads | 8 | ||
| Base Clock Rate | 3.4 GHz | 3.5 GHz | |
| Max. Turbo Boost Frequency | 3.8 GHz | 3.9 GHz | |
| Shared L3 Cache | 8 MB | ||
| Instruction Set Extensions | SSE4.1/4.2, AVX | SSE 4.1/4.2, AVX 2.0 | |
| Thermal Design Power | 95 W | 77 W | 84 W |
| Max. Memory | 32 GB, Unbuffered ECC DDR3 | ||
| Max. Memory Data Rate | DDR3-1066/1333 | DDR3-1333/1600 | |
| # of Memory Channels | 2 | ||
| Max. Memory Bandwidth | 21 GB/s | 25.6 GB/s | |
| Processor Graphics | HD Graphics P3000 | HD Graphics P4000 | HD Graphics P4600 |
| Graphics Base Frequency | 850 MHz | 650 MHz | 350 MHz |
| Graphics Max. Dynamic Frequency | 1.35 GHz | 1.25 GHz | 1.25 GHz |
| # of Displays Supported | 2 | 3 | |
| PCI Express Revision | 2.0 | 3.0 | |
| Quick Sync Video | Yes | ||
| vPro | Yes | ||
| VT-x with EPT | Yes | ||
| VT-d | Yes | ||
| TXT | Yes | ||
| AES-NI | Yes | ||
| TSX-NI | No | Yes |
The changes from one launch to the next are apparent, and the most noteworthy evolution, ironically, might be processor-based graphics. Intel is leaning on its HD Graphics 4600 implementation; again, there are no Iris Pro 5200-equipped Xeons. The HD Graphics P4600 engine sports 20 execution units, or four more than the generation prior.
