CPU Comparison

The Intel Xeon X5492 and Intel Core i7-920 are two end-of-life processors from 2008 that deliver nearly identical application performance, but they achieve it through fundamentally different designs. Benchmark data shows the Xeon X5492 edges out the Core i7-920 in every single tested workload, with margins ranging from 1.2% to 1.5%. However, the Core i7-920 counters with architectural advantages in threading, memory bandwidth, and cache hierarchy that the raw scores do not fully capture. The Xeon X5492 wins on raw clock speed and single-threaded responsiveness, while the Core i7-920 offers a more modern platform foundation for multi-threaded and memory-intensive tasks.

Where Each One Wins

The Xeon X5492 wins in every benchmark category recorded, but the margins are razor-thin. In Cinebench R15 multicore, it scores 249 against 246 for the Core i7-920, a 1.2% advantage. The gap widens slightly in Cinebench R20 multicore (1039 vs 1025, +1.4%) and remains consistent in Cinebench R23 multicore (2475 vs 2442, +1.4%). Single-core tests show the same pattern: R20 single-core gives 146 vs 144 (+1.4%), and R23 single-core gives 349 vs 344 (+1.5%). This means the Xeon X5492 is the pick for any workload that relies on raw clock speed and per-thread execution, such as lightly-threaded legacy applications or tasks that cannot scale across many cores.

The Core i7-920, despite losing every head-to-head test, wins in architectural capability that the benchmarks do not measure directly. It has 8 threads versus 4 on the Xeon, a shared 8 MB L3 cache versus no L3 at all on the Xeon, and a triple-channel memory bus versus dual-channel on the Xeon. The data shows the Core i7-920 has a 22nd percentile ranking versus 23rd for the Xeon, meaning the Xeon sits marginally higher among all CPUs, but the Core i7-920's threading and memory advantages suggest it could outperform in workloads that the Cinebench suite does not stress, such as video encoding, database queries, or virtualized environments. The Core i7-920 also supports DDR3 memory only, while the Xeon supports both DDR2 and DDR3, giving the i7 a more streamlined memory path.

Architecture Differences

The two processors come from different Intel microarchitectures. The Xeon X5492 is built on the Core 2 architecture with the codename Harpertown, while the Core i7-920 uses the Nehalem architecture with codename Bloomfield. Both are manufactured on a 45 nm process node, but the dies differ significantly. The Xeon has a die size of 2x 107 mm² with 820 million transistors, whereas the Core i7-920 uses a single 263 mm² die with 731 million transistors. The Xeon's dual-die design reflects its server heritage, while the Core i7's monolithic die integrates more features per unit area.

Cache configurations are starkly different. The Xeon X5492 provides 64 KB of L1 cache per core and 6 MB of L2 cache per die, with no L3 cache at all. The Core i7-920 also has 64 KB of L1 per core, but its L2 is larger at 256 KB per core, and it adds a shared 8 MB L3 cache. This means the Core i7-920 can hold significantly more working data closer to the cores, reducing reliance on main memory. The Xeon's L2 is distributed across two dies, potentially increasing latency for cross-die data access.

Memory support diverges as well. The Xeon X5492 supports both DDR2 and DDR3 across a dual-channel bus, with ECC memory support enabled for server reliability. The Core i7-920 supports only DDR3 across a triple-channel bus, which provides higher theoretical bandwidth, but it lacks ECC support, marking it as a consumer desktop part. Both use PCIe Gen 2, and neither includes integrated graphics. The Xeon is a server/workstation part with a launch MSRP of $1493, while the Core i7-920's launch MSRP is not recorded in the data.

Head-to-Head Benchmarks

The head-to-head results are uniform: the Xeon X5492 wins all five recorded tests, but by margins that are within normal run-to-run variance. In Cinebench R15 multicore, the Xeon scores 249 versus 246 for the Core i7-920, a 1.2% delta. The R20 multicore test shows 1039 versus 1025, a 1.4% advantage for the Xeon. The R23 multicore test delivers 2475 versus 2442, also a 1.4% gap. Single-core results follow the same trend: R20 single-core at 146 versus 144 (+1.4%) and R23 single-core at 349 versus 344 (+1.5%).

The largest single delta is 1.5% in Cinebench R23 single-core, where the Xeon's 3.40 GHz base clock outperforms the Core i7-920's 2.67 GHz base clock and 2.93 GHz boost clock. In multi-core tests, the Xeon's clock advantage compensates for its lack of hyper-threading, but only barely. The Core i7-920's 8 threads should theoretically give it a multi-threaded edge, but the data shows the Xeon's higher clock speed and more efficient Core 2 pipeline hold the lead. The average benchmark score for the Xeon is 852 against 840 for the Core i7-920, a 1.4% overall difference that matches the individual test deltas.

The Xeon's nearest rivals include the Intel Core i5-5250U (avg score 856, delta -0.4%), Intel Core i5-2500T (avg score 856, delta -0.5%), and Intel Core i7-4500U (avg score 859, delta -0.8%), all of which are newer mobile parts that slightly exceed the Xeon. The Core i7-920's nearest rivals include the Intel Xeon X5470 (avg score 839, delta 0.1%), Intel Core i5-3380M (avg score 838, delta 0.2%), and AMD FX-8800P (avg score 843, delta -0.3%), showing the i7 sits in a similar performance bracket.

The Verdict

The data directs a clear split recommendation. For users running single-threaded or lightly-threaded workloads where clock speed dominates, the Intel Xeon X5492 is the correct choice. It wins every benchmark in the record, and its 3.40 GHz base clock provides a decisive advantage in Cinebench R23 single-core (349 vs 344) and R20 single-core (146 vs 144). The Xeon also carries ECC memory support, making it suitable for workstation or server environments where data integrity is critical.

For users whose workloads scale across many threads, the Intel Core i7-920 is the more future-proof pick despite losing the recorded tests. Its 8 threads versus 4 on the Xeon, shared 8 MB L3 cache, and triple-channel memory bus provide architectural headroom that the Cinebench suite does not fully exercise. The 1.4% average score deficit is a small price for the ability to handle multi-threaded applications, virtual machines, or memory-bandwidth-sensitive tasks. The Core i7-920 also uses a single die with a smaller transistor count (731 million vs 820 million), which may indicate lower power consumption per thread, though the TDP figures show 130 W for the i7 versus 150 W for the Xeon.

The Xeon X5492 excels in raw per-core performance and server reliability features, while the Core i7-920 offers superior threading, cache, and memory bandwidth. Neither processor is a clear winner for all tasks; the choice hinges on whether the workload prioritizes clock speed or thread count.

FAQ

Q: Which processor has a higher single-core score in Cinebench R23?

A: The Intel Xeon X5492 scores 349 in Cinebench R23 single-core, while the Intel Core i7-920 scores 344, giving the Xeon a 1.5% advantage.

Q: How many threads does each processor support?

A: The Intel Xeon X5492 supports 4 threads (4 cores, no hyper-threading), while the Intel Core i7-920 supports 8 threads (4 cores with hyper-threading).

Q: Does either processor include integrated graphics?

A: No, neither the Intel Xeon X5492 nor the Intel Core i7-920 includes integrated graphics, according to the specification data.

Q: What memory types does each processor support?

A: The Intel Xeon X5492 supports both DDR2 and DDR3 memory across a dual-channel bus with ECC support. The Intel Core i7-920 supports only DDR3 across a triple-channel bus without ECC support.

Q: What is the difference in average benchmark scores?

A: The Intel Xeon X5492 has an average benchmark score of 852, while the Intel Core i7-920 scores 840, a difference of 12 points (1.4%).

Q: Which processor has a larger cache?

A: The Intel Core i7-920 has a larger cache configuration, with 256 KB of L2 per core and 8 MB of shared L3, whereas the Intel Xeon X5492 has 6 MB of L2 per die and no L3 cache.

Specification Differences

| Specification | Intel Xeon X5492 | Intel Core i7-920 |

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

| Base Clock | 3.40 GHz | 2.67 GHz |

| Boost Clock | None | 2.93 GHz |

| Threads | 4 | 8 |

| TDP | 150 W | 130 W |

| Socket | Intel Socket 771 | Intel Socket 1366 |

| Architecture | Core 2 | Nehalem |

| Codename | Harpertown | Bloomfield |

| Transistors | 820 million | 731 million |

| Die Size | 2x 107 mm² | 263 mm² |

| L2 Cache | 6 MB (per die) | 256 KB (per core) |

| L3 Cache | None | 8 MB (shared) |

| Memory Support | DDR2, DDR3 | DDR3 |

| Memory Bus | Dual-channel | Triple-channel |

| ECC Memory | Yes | No |

| Market Segment | Server/Workstation | Desktop |

| Launch MSRP | $1493 | Not recorded |

| Part Number | SLBBD | SLBCHSLBEJ |