Intel Core i5-2500S vs Intel Core i7-2635QM Comparison

The Intel Core i7-2635QM and Intel Core i5-2500S are both Sandy Bridge parts from the same 32 nm generation, but they target different market segments: the i7-2635QM is a mobile processor on Intel BGA 1224, while the i5-2500S is a desktop chip on Intel Socket 1155. The benchmark data shows a clear split: the i7-2635QM wins all five Cinebench tests, while the i5-2500S dominates both Geekbench tests. The i7-2635QM leads by margins of 4.4% to 4.7% in Cinebench R15, R20, and R23 workloads, whereas the i5-2500S counters with a 9.3% lead in Geekbench multi-core and a substantial 24.1% advantage in Geekbench single-core. With the i7-2635QM holding 5 wins and the i5-2500S taking 2, the overall average benchmark scores are nearly tied at 995 for the i7 and 1004 for the i5, placing both at the 27th percentile of all CPUs. The choice between them depends entirely on whether the workload resembles Cinebench's thread-heavy rendering or Geekbench's mixed single-threaded tasks.

The Verdict

From the data, the Intel Core i7-2635QM is the pick for multi-threaded rendering workloads. It wins every Cinebench test in the head-to-head comparison, with its strongest margin being a 4.7% lead in Cinebench R20 single-core (177 vs 169). Its advantage in Cinebench R23 multi-core is 4.5% (2995 vs 2867), and it holds a 4.5% edge in Cinebench R15 multi-core (301 vs 288). The i7-2635QM achieves this despite a lower base clock of 2000 MHz and boost clock of 2.90 GHz, relying on its 8 threads versus the i5-2500S's 4 threads.

The Intel Core i5-2500S is the better choice for mixed and single-threaded workloads, as measured by Geekbench. It posts a 24.1% higher single-core score (582 vs 442) and a 9.3% higher multi-core score (1511 vs 1371). Its higher clock speeds — 2.70 GHz base and 3.70 GHz boost — clearly drive these wins, and its desktop form factor with PCIe Gen 3, 16 Lanes (CPU only) support gives it a platform advantage for discrete graphics.

For users prioritizing Cinebench-style rendering, the i7-2635QM is the data-backed choice. For users needing the fastest possible single-thread performance and Geekbench responsiveness, the i5-2500S wins decisively. The overall average scores are nearly identical (995 vs 1004, a 0.9% difference), so the decision should be based on the specific benchmark family that matches the intended use case.

FAQ

Q: Which processor wins more head-to-head benchmark comparisons?

A: The Intel Core i7-2635QM wins 5 of the 7 head-to-head tests, while the Intel Core i5-2500S wins 2.

Q: How large is the single-core performance gap in Geekbench?

A: The Intel Core i5-2500S leads by 24.1% in Geekbench single-core, scoring 582 versus the i7-2635QM's 442.

Q: Does the i7-2635QM win any single-core tests?

A: Yes, the i7-2635QM wins Cinebench R20 single-core (177 vs 169, a 4.7% lead) and Cinebench R23 single-core (422 vs 404, a 4.5% lead).

Q: What is the difference in thread counts?

A: The Intel Core i7-2635QM has 8 threads, while the Intel Core i5-2500S has 4 threads. Both have 4 cores.

Q: Which processor has the higher boost clock?

A: The Intel Core i5-2500S has a boost clock of 3.70 GHz, compared to the i7-2635QM's 2.90 GHz.

Q: Are the overall average benchmark scores similar?

A: Yes, the i7-2635QM has an average benchmark score of 995, while the i5-2500S scores 1004, a difference of less than 1%.

Architecture Differences

Both processors share the same Sandy Bridge architecture, manufactured on Intel's 32 nm process node with a die size of 216 mm² and 1,160 million transistors. The L1 cache is 64 KB per core, L2 is 256 KB per core, and L3 is 6 MB shared for both parts. The key architectural divergence is in threading: the i7-2635QM supports 8 threads via Hyper-Threading, while the i5-2500S is limited to 4 threads. This explains the i7's consistent wins in multi-threaded Cinebench tests despite its lower clock speeds.

The integrated graphics differ as well. The i7-2635QM features Intel HD 3000, while the i5-2500S uses Intel HD 2000. Both are from the same generation but the i7's integrated GPU is a tier higher. The memory bus is dual-channel for both, but the i5-2500S explicitly supports DDR3 memory, while the i7-2635QM's memory support is not listed. The i5-2500S also carries PCIe Gen 3, 16 Lanes (CPU only), a feature absent from the i7-2635QM's specifications. Neither processor supports ECC memory, and both have locked multipliers.

The market segment difference is fundamental: the i7-2635QM is a mobile part with a 45 W TDP on Intel BGA 1224, while the i5-2500S is a desktop part with a 65 W TDP on Intel Socket 1155. Both are end-of-life products, released within days of each other in January 2011. The i7-2635QM's part number is SR030, and the i5-2500S is SR009.

Specification Differences

The two processors differ in several key specification fields. The i7-2635QM has a base clock of 2000 MHz and a boost clock of 2.90 GHz, while the i5-2500S runs at 2.70 GHz base and 3.70 GHz boost — a 700 MHz higher base and 800 MHz higher boost for the desktop part. Thread count is 8 for the i7 versus 4 for the i5. TDP is 45 W for the mobile chip and 65 W for the desktop chip. The socket is Intel BGA 1224 for the i7-2635QM and Intel Socket 1155 for the i5-2500S.

Integrated graphics differ: Intel HD 3000 on the i7-2635QM versus Intel HD 2000 on the i5-2500S. The memory support field is null for the i7-2635QM but lists DDR3 for the i5-2500S. The PCIe field is null for the i7-2635QM but specifies "Gen 3, 16 Lanes(CPU only)" for the i5-2500S. The market segment is Mobile for the i7 and Desktop for the i5. The generation field distinguishes them as "Core i7 (Sandy Bridge)" versus "Core i5 (Sandy Bridge)". Neither has a launch MSRP listed, and both have locked multipliers.

Head-to-Head Benchmarks

The head-to-head data reveals a complete split between the two benchmark families. In Cinebench R15 multi-core, the i7-2635QM scores 301 against the i5-2500S's 288, a 4.5% win. Cinebench R20 multi-core shows a similar pattern: 1257 vs 1204, a 4.4% margin. The i7-2635QM also wins Cinebench R20 single-core (177 vs 169, 4.7%) and Cinebench R23 single-core (422 vs 404, 4.5%). Cinebench R23 multi-core is the largest absolute score for the i7 at 2995, beating the i5's 2867 by 4.5%.

The i5-2500S takes the Geekbench tests decisively. In Geekbench multi-core, it scores 1511 versus the i7-2635QM's 1371, a 9.3% advantage. The single-core Geekbench gap is even larger: 582 vs 442, a 24.1% margin. This is the single biggest delta in the entire comparison. Notably, the i7-2635QM wins all Cinebench tests by margins between 4.4% and 4.7%, while the i5-2500S wins Geekbench tests by margins of 9.3% and 24.1%. The i5's wins are larger but fewer, while the i7's wins are smaller but more numerous.

The average benchmark scores reflect this balance: the i7-2635QM averages 995, and the i5-2500S averages 1004. The nearest rivals for the i7-2635QM include the Intel Core i7-2920XM at 995 (0% delta) and the AMD Opteron 4226 at 995 (0% delta). The i5-2500S's nearest rivals include the Intel Core i5-4300M at 1004 (0% delta) and the Intel Core i7-5600U at 1005 (-0.1% delta). Both processors sit at the 27th percentile of all CPUs, confirming they are mid-pack performers in the broader market.

Where Each One Wins

The Intel Core i7-2635QM wins in every Cinebench workload, across both multi-core and single-core variants. This makes it the choice for rendering tasks that resemble Cinebench's test methodology — CPU-bound ray tracing and 3D rendering where thread count matters. Its 8 threads allow it to outperform the i5-2500S by 4.4% to 4.7% in these tests, despite a 700 MHz lower base clock. The consistency of these wins — nearly identical margins across R15, R20, and R23 — suggests a stable architectural advantage from Hyper-Threading rather than any workload-specific quirk.

The Intel Core i5-2500S wins in Geekbench, which is a more diverse set of workloads including encryption, compression, and memory operations. The 24.1% single-core lead is particularly striking, driven by its 3.70 GHz boost clock. For users running single-threaded applications, database queries, or legacy software that doesn't scale beyond one core, the i5-2500S is clearly superior. Its 9.3% multi-core Geekbench lead also indicates that even in multi-threaded Geekbench tasks, the higher clock speeds outweigh the i7's extra threads.

The market segment tells the rest of the story. The i7-2635QM's 45 W TDP and mobile socket make it suitable for laptops, where its multi-threaded Cinebench wins come at lower power consumption. The i5-2500S's 65 W TDP and desktop socket with PCIe Gen 3 16 lanes make it a better foundation for a desktop system with discrete graphics, where its Geekbench wins and higher clocks are more valuable. The i7-2635QM's Intel HD 3000 graphics are a step above the i5-2500S's HD 2000, but the desktop platform's PCIe support offers a path to external GPUs that the mobile BGA socket cannot match. Ultimately, the data supports the i7-2635QM for Cinebench-style rendering and the i5-2500S for Geekbench-style general computing.