Intel Core i7-870S vs Intel Xeon X3440 Comparison

FAQ

Q: Which processor has the higher boost clock?

A: The Intel Core i7-870S boosts to 3.60 GHz, significantly higher than the Intel Xeon X3440's 2.93 GHz boost. However, the Xeon has a lower base clock of 2.53 GHz versus the i7-870S's 2.67 GHz.

Q: Do these two CPUs share the same architecture and process node?

A: Yes. Both are built on Intel's 45 nm Nehalem architecture with the Lynnfield codename. Both pack 774 million transistors on a 296 mm² die.

Q: Which chip supports ECC memory?

A: Only the Intel Xeon X3440 supports ECC memory. The Core i7-870S does not, reflecting its desktop market positioning versus the Xeon's server/workstation segment.

Q: How do they compare in multi-core Cinebench R23?

A: The Xeon X3440 scores 2368, edging out the i7-870S's 2350 by 0.8%. It's a narrow win, but consistent across all tested workloads.

Q: What is the average benchmark score difference between them?

A: The Xeon X3440 averages 815 across benchmarks, while the i7-870S averages 809. That's a 0.7% gap in favor of the Xeon.

Q: Which processor was released later?

A: The Core i7-870S launched on 2010-07-18, about ten months after the Xeon X3440's 2009-09-07 release date.

Architecture Differences

Both CPUs are fundamentally the same silicon: Nehalem architecture, Lynnfield codename, 45 nm process, 774 million transistors, and a 296 mm² die. They share identical cache hierarchies — 64 KB L1 per core, 256 KB L2 per core, and 8 MB shared L3. Both run on Intel Socket 1156 with PCIe Gen 2 (16 lanes, CPU only) and dual-channel DDR3 memory.

The key architectural divergence is memory support. The Xeon X3440 enables ECC memory with a rated memory bandwidth of 21.3 GB/s, a feature absent on the Core i7-870S, which lists no memory bandwidth figure. This reflects their target markets: the Xeon is a Server/Workstation part, while the i7-870S is a Desktop chip.

Clock behavior separates them further. The i7-870S runs a 2.67 GHz base but boosts to 3.60 GHz — a 0.93 GHz boost window. The Xeon starts lower at 2.53 GHz and boosts only to 2.93 GHz, a narrower 0.40 GHz range. Despite the i7-870S's higher clocks, its TDP is lower at 82 W versus the Xeon's 95 W. This suggests the i7-870S leverages a more aggressive boost strategy while maintaining efficiency, whereas the Xeon prioritizes sustained server workloads within a higher power envelope.

Both chips lack integrated graphics and have locked multipliers. The Xeon X3440 carries part number SLBLF, while the i7-870S uses SLBQ7. The Xeon was announced with a launch MSRP of $215; no launch MSRP is listed for the i7-870S.

Head-to-Head Benchmarks

The data shows a clean sweep: the Intel Xeon X3440 wins all five head-to-head Cinebench comparisons, though by margins so thin they border on statistical noise.

In Cinebench R15 multi-core, the Xeon scores 238 against the i7-870S's 236, a 0.8% delta. The R20 multi-core test narrows slightly: 994 versus 987, a 0.7% gap. Single-core results follow the same pattern — R20 single-core gives the Xeon 140 against 139 (0.7%), and R23 single-core shows 334 versus 331 (0.9%).

The largest relative win comes in R23 multi-core, where the Xeon's 2368 beats 2350 by 0.8%. Interestingly, the Xeon wins every test despite the i7-870S having a 0.67 GHz higher boost clock. This suggests the Xeon's ECC memory support or server-oriented power management may offset the clock disadvantage in these workloads, or that the i7-870S's boost is thermally constrained in sustained multi-core runs.

Looking at average benchmark scores, the Xeon's 815 edges the i7-870S's 809 by 0.7%. Both sit at the 22nd percentile among all CPUs, placing them in the same performance tier. The Xeon's nearest rivals include the Intel Core i5-L16G7 (816, -0.1%), Intel Core 2 Extreme QX9775 (813, +0.2%), Intel Core i7-5550U (813, +0.2%), and Intel Xeon E5540 (820, -0.7%). The i7-870S's rivals are the AMD A10-6800K (809, 0%), AMD Athlon X4 850 (806, +0.4%), Intel Xeon X5482 (805, +0.4%), and Intel Core 2 Extreme QX9775 (813, -0.5%).

The practical takeaway: these CPUs are effectively tied in Cinebench performance. The Xeon's largest margin is 0.9% — a difference that would be imperceptible in real-world use. Neither chip offers a meaningful performance advantage over the other in these benchmarks.

The Verdict

The data presents a straightforward case: the Intel Xeon X3440 is the marginally faster processor in every tested Cinebench workload, but the margins are so small (0.7% to 0.9%) that they carry no practical significance. Both chips land at the 22nd percentile, reinforcing their equivalence.

Choose the Xeon X3440 if your workload requires ECC memory support. That's the only material differentiator in the benchmark data — the Xeon's 21.3 GB/s memory bandwidth rating and server/workstation market segment suggest it's built for data integrity in multi-socket or reliability-critical environments. The 0.7% average score advantage is a rounding error compared to the ECC feature.

Choose the Core i7-870S if you're building a desktop system where lower power consumption matters. Its 82 W TDP versus the Xeon's 95 W represents a 13 W savings, which could simplify cooling requirements. The i7-870S also boosts to 3.60 GHz, which might offer headroom for lightly-threaded tasks, though the Cinebench single-core results show no actual advantage — the Xeon still wins by 0.7-0.9%.

For anyone deciding between these two on performance alone, the data says it doesn't matter. The Xeon's 5-0 win record in head-to-head tests is technically a victory, but a 0.8% average delta is within run-to-run variance. The real decision hinges on ECC support (Xeon) versus lower TDP (i7-870S).

Given that both are end-of-life products on the same socket with identical core/thread counts and cache, the market segment is the only meaningful differentiator. The Xeon targets reliability; the i7-870S targets efficiency. Neither offers a performance edge worth paying a premium for.

Specification Differences

| Specification | Intel Xeon X3440 | Intel Core i7-870S |

|---|---|---|

| Base Clock | 2.53 GHz | 2.67 GHz |

| Boost Clock | 2.93 GHz | 3.60 GHz |

| TDP | 95 W | 82 W |

| Memory Bandwidth | 21.3 GB/s | Not specified |

| ECC Memory | Yes | No |

| Market Segment | Server/Workstation | Desktop |

| Release Date | 2009-09-07 | 2010-07-18 |

| Launch MSRP | $215 | Not specified |

| Part Number | SLBLF | SLBQ7 |

The remaining specifications are identical: 4 cores, 8 threads, 45 nm process, 774 million transistors, 296 mm² die, 64 KB L1 per core, 256 KB L2 per core, 8 MB shared L3, dual-channel DDR3, PCIe Gen 2 with 16 lanes, Intel Socket 1156, and no integrated graphics. Both are locked multipliers and end-of-life products. The Xeon holds a launch MSRP of $215; the i7-870S has no listed launch MSRP.