AMD EPYC 7742 vs Intel Core i5-1235U Comparison

The Intel Core i5-1235U and the AMD EPYC 7742 are fundamentally different processors, and the benchmark data reflects that divide with absolute clarity. The EPYC 7742, a 64-core server behemoth, wins every single head-to-head benchmark in this comparison by a margin of roughly 83%, while the i5-1235U, a 10-core mobile chip, counters with a significantly lower power envelope and integrated graphics. This is not a contest of equals; it is a demonstration of two extreme ends of the processor spectrum, where the data shows the EPYC 7742 dominating in raw throughput while the i5-1235U occupies a completely different performance and power class.

FAQ

Q: Which processor is faster in multi-core performance?

A: The AMD EPYC 7742 is overwhelmingly faster. In Cinebench R23 multi-core, it scores 58,769 points compared to the Intel Core i5-1235U's 9,774 points, a delta of -83.4% for the Intel part.

Q: Does the Intel i5-1235U win any benchmark in this comparison?

A: No. The head-to-head data shows the AMD EPYC 7742 winning all six benchmark tests, covering both multi-core and single-core workloads across Cinebench R15, R20, and R23.

Q: How do their core and thread counts compare?

A: The AMD EPYC 7742 has 64 cores and 128 threads, while the Intel Core i5-1235U has 10 cores and 12 threads. This 64-core count is a primary driver of the EPYC's massive multi-core advantage.

Q: What are the key architectural differences between the two?

A: The Intel i5-1235U is built on Intel's Alder Lake architecture using a 10 nm process, while the AMD EPYC 7742 uses AMD's Zen 2 architecture on a 7 nm process from TSMC. They also use entirely different sockets: Intel BGA 1744 for the i5 and AMD Socket SP3 for the EPYC.

Q: Which processor has more cache?

A: The AMD EPYC 7742 has a substantially larger L3 cache at 256 MB (shared), compared to the Intel Core i5-1235U's 12 MB (shared). The EPYC also has 96 KB of L1 cache per core versus 80 KB per core for the Intel.

Q: Do both processors support ECC memory?

A: No. The AMD EPYC 7742 supports ECC memory, a critical feature for server workloads, while the Intel Core i5-1235U does not support ECC memory.

Architecture Differences

The architectural gap between these two processors is vast, starting with their fundamental design goals. The Intel Core i5-1235U is a mobile processor from the Alder Lake-U family, built on a 10 nm process at Intel. It features a hybrid architecture with 10 cores and 12 threads, a configuration designed for power efficiency in laptops. In contrast, the AMD EPYC 7742 is a server-class part from the EPYC 7002 series, codenamed Rome, built on a 7 nm process at TSMC. It is a monolithic design with 64 cores and 128 threads, engineered for maximum throughput in data centers.

The memory subsystems also differ drastically. The Intel i5-1235U supports both DDR4 and DDR5 memory with a dual-channel bus, while the AMD EPYC 7742 exclusively supports DDR4 but over an eight-channel memory bus. The EPYC's memory bandwidth is listed at 204.8 GB/s, a figure that reflects its server positioning. The Intel part lacks a listed memory bandwidth figure, but its dual-channel configuration is clearly designed for lower-power mobile use.

Cache hierarchies further underscore the divide. The Intel i5-1235U has 80 KB of L1 cache per core, 1.25 MB of L2 cache per core, and 12 MB of shared L3 cache. The AMD EPYC 7742, by contrast, has 96 KB of L1 per core, 512 KB of L2 per core, and a massive 256 MB of shared L3 cache. The EPYC also carries 3,800 million transistors on a 74 mm² die, while the Intel part does not list transistor or die size data. The EPYC supports ECC memory and PCIe Gen 4, while the Intel part supports PCIe Gen 4 with 20 lanes (CPU only) and includes integrated Iris Xe 80EU graphics, which the EPYC lacks entirely.

Head-to-Head Benchmarks

The benchmark results are unambiguous: the AMD EPYC 7742 wins every single test in the head-to-head comparison. In Cinebench R15 multi-core, the EPYC scores 5,923 against the i5-1235U's 985, a delta of -83.4% for the Intel chip. The single-core R15 test shows a similar pattern, with the EPYC at 836 and the Intel at 138, also a -83.5% delta. These margins are not slight; they represent a six-fold difference in performance.

Moving to Cinebench R20, the EPYC 7742 scores 24,682 in multi-core, dwarfing the i5-1235U's 4,105, again a -83.4% delta. The single-core R20 result shows the EPYC at 3,484 versus 579 for the Intel, maintaining the consistent -83.4% gap. In Cinebench R23, the most demanding test, the EPYC 7742 posts 58,769 multi-core points, while the i5-1235U manages 9,774, a delta of -83.4%. The R23 single-core test follows suit, with the EPYC at 8,296 and the Intel at 1,379, a -83.4% delta.

The data reveals that the EPYC 7742's dominance is not just in multi-threaded workloads, where its 64 cores would naturally excel, but also in single-threaded performance. The EPYC's 3.40 GHz boost clock, while lower than the Intel's 4.40 GHz boost, still delivers a single-core score that is roughly six times higher in every Cinebench iteration. This suggests that the Zen 2 architecture in the EPYC, despite its server focus, is more efficient per clock in these tests than the Alder Lake mobile chip.

Specification Differences

The two processors differ in nearly every measurable specification, reflecting their entirely different market segments. The Intel Core i5-1235U has 10 cores and 12 threads, a base clock of 1300.00 MHz, and a boost clock of 4.40 GHz, with a thermal design power (TDP) of 15 watts. The AMD EPYC 7742 has 64 cores and 128 threads, a base clock of 2.25 GHz, a boost clock of 3.40 GHz, and a TDP of 225 watts. The EPYC's TDP is 15 times higher, a direct consequence of its massive core count.

The sockets are incompatible: the Intel part uses Intel BGA 1744, while the AMD part uses AMD Socket SP3. The architectures are from different generations, with the i5-1235U on Alder Lake and the EPYC 7742 on Zen 2 (Rome). The process nodes differ, with Intel at 10 nm and AMD at 7 nm. Memory support varies, with the Intel part supporting DDR4 and DDR5 on a dual-channel bus, and the AMD part supporting only DDR4 on an eight-channel bus, with a listed bandwidth of 204.8 GB/s. ECC memory is supported only by the AMD EPYC 7742. The Intel part has integrated Iris Xe 80EU graphics, while the AMD part has none. The market segments are explicitly different: Mobile for the Intel and Server/Workstation for the AMD.

The Verdict

The verdict from the data is categorical: the AMD EPYC 7742 is the superior processor in every benchmark listed. It wins all six head-to-head tests by a consistent margin of approximately 83.4%, and its 64 cores, 128 threads, and 256 MB of L3 cache make it a powerhouse for any compute-intensive, multi-threaded workload. The Intel Core i5-1235U, with its 10 cores, 12 threads, and 12 MB of L3 cache, is a low-power mobile chip that cannot compete on raw performance; its 15-watt TDP and integrated graphics are designed for a completely different use case. However, the EPYC 7742's 225-watt TDP and server socket mean it is not a practical choice for a laptop, just as the i5-1235U's mobile design would be wholly inadequate for a server. The choice is not about which is "better" in absolute terms, but which is appropriate for the intended platform.

Where Each One Wins

The AMD EPYC 7742 wins in every scenario where raw computational throughput is the primary requirement. Its 64 cores and 128 threads deliver a 58,769 score in Cinebench R23 multi-core, making it the clear choice for server virtualization, large-scale data processing, scientific computing, and any workload that can leverage massive parallelism. Its eight-channel memory bus with 204.8 GB/s bandwidth and ECC support further cement its role in enterprise environments where data integrity and memory capacity are critical. The EPYC's 256 MB of L3 cache is a significant asset for workloads with large working sets.

The Intel Core i5-1235U, conversely, wins in scenarios defined by power efficiency and portability. Its 15-watt TDP and integrated Iris Xe 80EU graphics make it suitable for thin-and-light laptops where battery life and thermal headroom are paramount. While its benchmark scores are far lower, its 4.40 GHz boost clock and support for DDR5 memory allow it to handle everyday productivity tasks, web browsing, and light content creation without requiring a dedicated GPU. The i5-1235U's wins are not in the benchmark data, but in its form factor and power profile, which are not measured in the Cinebench tests. The data shows a clear division: the EPYC 7742 for maximum compute, the i5-1235U for mobile efficiency.