Intel Core i5-5350U vs Intel Core i7-940 Comparison

# Intel Core i7-940 vs Intel Core i5-5350U

The Intel Core i7-940 and Intel Core i5-5350U are both end-of-life processors, but they occupy opposite ends of the desktop-to-mobile spectrum. The i7-940 is a 45nm Bloomfield desktop chip from late 2008, while the i5-5350U is a 14nm Broadwell-U mobile part from early 2015. Despite the seven-year gap, their average benchmark scores are identical at 903, and both sit at the 24th percentile of all CPUs. The head-to-head data, however, tells a one-sided story: the i7-940 wins all five shared Cinebench tests with margins between 19.2% and 19.5%. This makes the choice less about raw capability and more about platform context.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Core i7-940 has 4 cores and 8 threads, while the Intel Core i5-5350U has 2 cores and 4 threads. The i7-940 doubles both counts, which directly contributes to its multicore lead.

Q: How do their average benchmark scores compare?

A: Both chips have an identical average benchmark score of 903. They also share the same 24th percentile ranking against all CPUs, meaning they sit at the same overall performance tier despite their architectural differences.

Q: What is the biggest performance gap in head-to-head testing?

A: The largest margin is 19.5%, seen in both Cinebench R15 multicore (264 vs 221) and Cinebench R23 multicore (2626 vs 2198). The i7-940 wins every shared test, with no wins for the i5-5350U.

Q: Does the i5-5350U have integrated graphics?

A: Yes, the Intel Core i5-5350U includes Intel HD 6000 graphics. The Intel Core i7-940 has no integrated graphics, meaning it requires a discrete GPU for any display output.

Q: What are the TDP differences between these two chips?

A: The i7-940 has a TDP of 130 watts, while the i5-5350U has a TDP of 15 watts. This 115-watt gap reflects the desktop versus ultra-low-power mobile design philosophy.

Q: Which processor has a higher boost clock?

A: The i7-940 boosts to 3.20 GHz, while the i5-5350U boosts to 2.90 GHz. However, the i5-5350U has a much higher base clock figure of 1800.00 MHz listed, though this appears to be an artifact of how the base clock is reported.

Where Each One Wins

The Intel Core i7-940 wins in every benchmark category where both chips were tested. Looking at the head-to-head results, the i7-940 takes all five Cinebench tests: R15 multicore, R20 multicore, R20 singlecore, R23 multicore, and R23 singlecore. The i5-5350U has zero wins in shared tests. This means the i7-940 is the clear choice for any workload that relies on Cinebench-style rendering or compute performance.

However, the i5-5350U has its own territory. It is the only one of the two with integrated graphics (Intel HD 6000), making it viable in compact, fanless, or low-power systems where a discrete GPU is impractical. Its 15-watt TDP versus the i7-940's 130-watt TDP means it can run in thin-and-light laptops or mini PCs without exotic cooling. The i5-5350U also has a much smaller die size at 133 mm² versus 263 mm², and it was built on a 14nm process versus 45nm, which speaks to efficiency improvements.

For mobile users, the i5-5350U's dual-channel memory bus and 29.9 GB/s memory bandwidth (a spec the i7-940 lacks in the data) are relevant. The i7-940 uses triple-channel DDR3, which offers more memory channels but at the cost of motherboard complexity and power.

Architecture Differences

The architecture gap between these two is generational. The i7-940 uses the Nehalem architecture with the Bloomfield codename, built on a 45nm process at Intel's foundry. It packs 731 million transistors into a 263 mm² die. The i5-5350U uses the Broadwell architecture with the Broadwell-U codename, built on a 14nm process. It contains 1,900 million transistors in a much smaller 133 mm² die. That is roughly 2.6 times more transistors in half the area, illustrating the density leap from 45nm to 14nm.

Cache configurations differ notably. Both share 64 KB of L1 cache per core and 256 KB of L2 cache per core. The L3 cache, however, is where the i7-940 pulls ahead: it has 8 MB shared, while the i5-5350U has only 3 MB shared. This 5 MB difference can matter in workloads with large working sets that benefit from on-die caching.

The i7-940 supports triple-channel memory, while the i5-5350U uses dual-channel. Both support DDR3, and neither supports ECC memory. The i5-5350U includes integrated Intel HD 6000 graphics; the i7-940 has none. PCIe support is Gen 2 for both, but the i5-5350U specifies 12 lanes (CPU only), while the i7-940 does not list a lane count.

Specification Differences

The two processors differ across nearly every core specification. Core count: 4 versus 2. Thread count: 8 versus 4. Base clock: 2.93 GHz (i7-940) versus 1800.00 MHz (i5-5350U). Boost clock: 3.20 GHz versus 2.90 GHz. TDP: 130 watts versus 15 watts. Socket: Intel Socket 1366 versus Intel BGA 1168. Process node: 45nm versus 14nm. Transistor count: 731 million versus 1,900 million. Die size: 263 mm² versus 133 mm².

L3 cache is 8 MB shared versus 3 MB shared. Memory bus is triple-channel versus dual-channel. The i5-5350U lists a memory bandwidth of 29.9 GB/s; the i7-940 has no such figure in the data. Integrated graphics: none versus Intel HD 6000. Market segment: Desktop versus Mobile. Release date: November 2008 versus February 2015. Part numbers: SLBCK versus SR268. The i5-5350U has a launch MSRP of $315; the i7-940 has no launch MSRP listed.

Head-to-Head Benchmarks

The head-to-head results are remarkably consistent. In Cinebench R15 multicore, the i7-940 scores 264 against the i5-5350U's 221, a 19.5% advantage. Cinebench R20 multicore shows 1102 versus 923, a 19.4% lead. Single-core results follow the same pattern: R20 singlecore is 155 versus 130 (19.2% ahead), and R23 singlecore is 370 versus 310 (19.4% ahead). The largest absolute gap is in Cinebench R23 multicore, where the i7-940 scores 2626 versus 2198, a difference of 428 points.

The consistency of the margins — all between 19.2% and 19.5% — suggests that the i7-940's advantage scales uniformly across both single-threaded and multi-threaded workloads. This is notable because the i5-5350U has a higher base clock (1800.00 MHz) but a lower boost clock (2.90 GHz versus 3.20 GHz). The i7-940 also benefits from 8 threads versus 4, and 8 MB of L3 versus 3 MB, which helps in both single and multicore Cinebench tests.

The i5-5350U does have additional benchmarks not shared with the i7-940: Geekbench multicore at 1671 and Geekbench singlecore at 868. These are not part of the head-to-head comparison, but they exist in the data as reference points. The i7-940 has no Geekbench results listed.

The Verdict

Based strictly on the data, the Intel Core i7-940 is the faster processor in every shared benchmark. It wins all five Cinebench tests with margins near 19.5%, and it offers double the cores, double the threads, and more than double the L3 cache (8 MB versus 3 MB). If your priority is raw compute performance in rendering or CPU-bound tasks, the i7-940 is the clear pick.

The Intel Core i5-5350U, however, is not without merit. Its 15-watt TDP makes it suitable for systems where power draw and heat are the primary constraints. Its integrated Intel HD 6000 graphics eliminate the need for a separate GPU. Its 14nm process and 1,900 million transistors in a 133 mm² die represent a much more modern and efficient design. For a mobile or ultra-compact build, the i5-5350U is the only one of the two that makes sense.

The identical average benchmark score of 903 and the shared 24th percentile ranking indicate that, in aggregate, these chips perform at the same level. But that aggregate hides the fact that the i7-940 dominates the specific tests both chips took. The i5-5350U's Geekbench scores — 1671 multicore and 868 singlecore — are not directly comparable to the Cinebench results, so they do not change the head-to-head picture.

Choose the i7-940 if you need desktop-class multicore performance and have a platform that can handle a 130-watt TDP. Choose the i5-5350U if you need a low-power, graphics-integrated chip for a mobile or compact system. The data does not support choosing the i5-5350U for performance reasons — it wins no shared benchmarks — but it wins on efficiency and integration.