CPU Comparison

The Intel Core i7-960 and Intel Core i7-875K are both 45 nm Nehalem-based quad-core processors with eight threads, but they target different platforms and exhibit distinct performance profiles. The i7-960, a Bloomfield part for Socket 1366, consistently outperforms the i7-875K (Lynnfield, Socket 1156) across all recorded Cinebench benchmarks, with margins ranging from 5.5% to 5.7%. The i7-875K counters with a lower 95 W TDP, an unlocked multiplier, and a higher boost clock of 3.60 GHz, positioning it as a more flexible and power-efficient option despite its lower average benchmark score.

FAQ

Q: Which processor has the higher base clock speed?

A: The Intel Core i7-960 operates at a base clock of 3.20 GHz, while the Intel Core i7-875K has a base clock of 2.93 GHz. The i7-960 holds a 0.27 GHz advantage in this metric.

Q: How do the two chips compare in multi-core performance?

A: The i7-960 leads in all multi-core tests. In Cinebench R15 multicore, it scores 290 versus 275 for the i7-875K, a 5.5% advantage. In Cinebench R20 multicore, the i7-960 scores 1211 against 1146, and in Cinebench R23 multicore, it scores 2885 versus 2729, both representing a 5.7% lead.

Q: Does the i7-875K have any performance advantage over the i7-960?

A: No. In the head-to-head benchmark data, the i7-960 wins all five recorded tests (Cinebench R15/R20/R23 multicore and R20/R23 singlecore). The i7-875K has zero wins in this comparison.

Q: What is the difference in memory bus configuration between the two?

A: The i7-960 supports triple-channel DDR3 memory, while the i7-875K supports dual-channel DDR3 memory. The i7-875K has a specified memory bandwidth of 21.3 GB/s, whereas the i7-960's memory bandwidth is not listed in the data.

Q: Are these processors unlocked for overclocking?

A: The Intel Core i7-875K has an unlocked multiplier (multiplierUnlocked: true), making it the only one of the two designed for easy overclocking. The Intel Core i7-960 has a locked multiplier (multiplierUnlocked: false).

Q: How do their average benchmark scores and percentiles compare?

A: The i7-960 has an average benchmark score of 993 and sits at the 27th percentile of all CPUs. The i7-875K has an average benchmark score of 984 and also sits at the 27th percentile. The i7-960's nearest rival is the Intel Core i7-965 with a 0% delta, while the i7-875K's nearest rival is the Intel Core i3-4130T with a 0% delta.

Architecture Differences

Both processors are built on Intel's Nehalem architecture and fabricated on a 45 nm process node, but they belong to different sub-families. The i7-960 uses the Bloomfield codename and is part of the Core i7 (Bloomfield) generation, while the i7-875K uses the Lynnfield codename and is part of the Core i7 (Lynnfield) generation. This distinction is not merely cosmetic; it reflects changes in the memory controller and platform integration.

The most significant architectural divergence is the memory bus. The i7-960 features a triple-channel DDR3 memory interface, whereas the i7-875K employs a dual-channel DDR3 interface. This means the i7-960 can access memory across three channels simultaneously, potentially reducing latency and increasing throughput in memory-sensitive workloads, even though the i7-875K does have a published memory bandwidth figure of 21.3 GB/s.

Cache hierarchies are identical in structure and size: each core has 64 KB of L1 cache and 256 KB of L2 cache, with a shared 8 MB L3 cache for both chips. The transistor count and die size differ slightly, however. The i7-875K contains 774 million transistors on a 296 mm² die, while the i7-960 contains 731 million transistors on a 263 mm² die. This suggests the Lynnfield die integrates the dual-channel memory controller and PCIe lanes in a different configuration, likely contributing to its smaller footprint relative to transistor density.

Both processors lack integrated graphics and support DDR3 memory without ECC functionality. They also share the same PCIe generation (Gen 2), but the i7-875K specifies "16 Lanes (CPU only)" for PCIe, whereas the i7-960's PCIe lane configuration is not detailed in the data. This difference points to the i7-875K's design as a more streamlined, mainstream-platform part, while the i7-960 is positioned on the higher-end Socket 1366 platform with a broader memory bus.

Head-to-Head Benchmarks

The benchmark results paint a consistent picture: the i7-960 is faster in every recorded test, but the margins are narrow and uniform. In Cinebench R15 multicore, the i7-960 scores 290 against the i7-875K's 275, yielding a 5.5% advantage. This gap widens slightly to 5.7% in Cinebench R20 multicore, where the i7-960 posts 1211 versus 1146.

Single-core performance follows the same trend. In Cinebench R20 singlecore, the i7-960 scores 170, which is 5.6% higher than the i7-875K's 161. The Cinebench R23 singlecore test shows the i7-960 at 407 versus 385 for the i7-875K, a 5.7% difference. The consistency of these margins across both multi-core and single-core workloads is notable; the i7-960's advantage is not confined to one type of task but is systemic across the Cinebench suite.

The i7-960's higher base clock (3.20 GHz vs. 2.93 GHz) likely explains part of this lead, despite the i7-875K's higher boost clock (3.60 GHz vs. 3.47 GHz). The benchmark scores suggest that sustained single-core and multi-core performance under load favors the i7-960's higher base frequency, even though the i7-875K can boost to a higher peak frequency. The i7-875K's dual-channel memory bus may also contribute to its deficit in multi-core tests, where memory bandwidth can become a bottleneck.

In the aggregate, the i7-960's average benchmark score is 993, while the i7-875K's is 984. This 9-point difference is small in absolute terms but aligns with the per-test deltas. Both processors land in the 27th percentile of all CPUs, indicating they are roughly equivalent in overall standing among their peers, even though the i7-960 holds a consistent edge in direct comparisons.

Specification Differences

The two processors differ in several key specification fields. The base clock is 3.20 GHz for the i7-960 and 2.93 GHz for the i7-875K, while the boost clock is 3.47 GHz for the i7-960 and 3.60 GHz for the i7-875K. The i7-960 has a TDP of 130 W, significantly higher than the i7-875K's 95 W.

The sockets are incompatible: the i7-960 uses Intel Socket 1366, while the i7-875K uses Intel Socket 1156. The codenames differ (Bloomfield vs. Lynnfield), as do the part numbers (SLBEU for the i7-960, SLBS2 for the i7-875K). The i7-875K has an unlocked multiplier (true), whereas the i7-960 does not (false). The i7-875K also has a launch MSRP of $353, which can be stated once as the launch MSRP; the i7-960 has no launch MSRP listed.

Die size and transistor count diverge: the i7-960 is 263 mm² with 731 million transistors, while the i7-875K is 296 mm² with 774 million transistors. Memory support differs in channel count: triple-channel for the i7-960 and dual-channel for the i7-875K, with the latter having a specified memory bandwidth of 21.3 GB/s. The i7-875K's PCIe is listed as "Gen 2, 16 Lanes (CPU only)," while the i7-960's PCIe is simply "Gen 2."

Release dates are separated by roughly seven months: the i7-960 was released on 2009-10-19, and the i7-875K on 2010-05-29. Both are end-of-life desktop parts with no integrated graphics and no ECC memory support. The i7-875K has additional Geekbench scores (1696 multicore, 499 singlecore) that are not listed for the i7-960 in the data.

Where Each One Wins

The i7-960 is the clear winner in raw benchmark performance. It takes all five head-to-head wins, with a 5.5% to 5.7% advantage across Cinebench R15, R20, and R23 in both multicore and singlecore tests. This makes it the superior choice for applications that rely on sustained CPU throughput, such as rendering, video encoding, or any workload that scales with clock speed and memory bandwidth. Its triple-channel memory interface is a structural advantage that the i7-875K cannot match, even if the benchmark deltas are modest.

The i7-875K, however, wins in areas not captured by the Cinebench scores. Its unlocked multiplier makes it the more overclocking-friendly part, allowing users to push the base clock beyond stock settings more easily than with the locked i7-960. Its lower TDP of 95 W versus 130 W means it generates less heat and may be easier to cool in a compact system, though the data does not specify cooler requirements. The i7-875K also has a higher boost clock of 3.60 GHz, which could provide a peak-speed advantage in lightly threaded tasks if the workload triggers maximum turbo, though the single-core benchmark results do not reflect this in practice.

For platform flexibility, the i7-875K's Socket 1156 and dual-channel memory setup target a more mainstream audience, while the i7-960's Socket 1366 and triple-channel memory target an enthusiast or workstation segment. The i7-875K also has a documented launch MSRP of $353, which is a point of differentiation, but no pricing comparison is made here.

In summary, the i7-960 is the performance leader in every measured benchmark, making it the pick for compute-bound tasks. The i7-875K is the more power-efficient, overclockable, and potentially more accessible option, but it cedes the performance crown to the i7-960 in all direct comparisons.