AMD EPYC 7643 vs Intel Core i7-1355U Comparison

The Intel Core i7-1355U and AMD EPYC 7643 occupy opposite ends of the computing spectrum, yet their average benchmark scores are nearly identical—18,730 for the Intel and 18,697 for the AMD, a difference of just 0.2%. This surface-level parity is deceptive: the head-to-head results show a complete sweep, with the EPYC winning all six shared Cinebench tests by margins ranging from 72.2% to 87.2%. The data paints a picture of two processors designed for entirely different workloads, where the average score masks the EPYC's overwhelming dominance in multi-threaded and even single-threaded rendering tasks. The Intel chip, a 15 W mobile part with 10 cores, cannot compete with a 225 W server processor packing 48 cores, yet both land in the 73rd percentile of all CPUs—a reminder that percentile rankings reflect the broader market, not the chasm between these two specific designs.

Head-to-Head Benchmarks

The AMD EPYC 7643 wins every single head-to-head benchmark, and it does so by staggering margins. In Cinebench R23 multi-core, the EPYC scores 64,642 against the Intel's 8,286—a 87.2% gap that reflects the raw core-count advantage: 48 Zen 3 cores versus 10 Raptor Lake cores. The single-core R23 result is equally lopsided in relative terms: 9,126 versus 1,825, an 80% deficit for the Intel. This is notable because single-core performance is typically where lower-power mobile chips can shine; here, the EPYC's higher base clock of 2.30 GHz and boost of 3.60 GHz simply outclass the Intel's 1.70 GHz base, even though the Intel boosts to 5.00 GHz.

The pattern holds across all Cinebench versions. In R20 multi-core, the EPYC scores 27,149 versus 4,949, a 81.8% lead. The R20 single-core test shows the same 81.8% gap, with 3,832 versus 698. Even the oldest test, R15, shows a 78.6% multi-core margin (6,515 versus 1,393) and a 72.2% single-core margin (919 versus 255.5). The Intel's best showing is in R15 single-core, where it trails by "only" 72.2%, but that is still a massive disadvantage. The data is unambiguous: the EPYC 7643 is faster in every measured rendering scenario, and the margins are so large that they suggest fundamentally different performance classes, not mere incremental differences.

FAQ

Q: How does the average benchmark score of the Intel Core i7-1355U compare to the AMD EPYC 7643?

A: The Intel has an average benchmark score of 18,730, while the AMD scores 18,697. The delta is 0.2%, meaning the Intel is nominally ahead by a negligible margin, but this average masks the EPYC's complete victory in all head-to-head Cinebench tests.

Q: Which processor wins in multi-core Cinebench R23, and by how much?

A: The AMD EPYC 7643 wins decisively with a score of 64,642 versus the Intel's 8,286. This represents an 87.2% lead for the AMD, the largest margin in any shared benchmark.

Q: Does the Intel chip have any advantage in single-core performance?

A: No. In Cinebench R23 single-core, the AMD EPYC scores 9,126 against the Intel's 1,825, an 80% deficit for the Intel. The AMD also wins R20 and R15 single-core tests by 81.8% and 72.2%, respectively.

Q: What are the core and thread counts for each processor?

A: The Intel Core i7-1355U has 10 cores and 12 threads. The AMD EPYC 7643 has 48 cores and 96 threads, giving it a 4.8x core advantage and an 8x thread advantage.

Q: Are these processors intended for the same market segment?

A: No. The Intel is a mobile processor (15 W TDP) with integrated Iris Xe Graphics, while the AMD is a server/workstation part (225 W TDP) with no integrated graphics. Their sockets are also different: Intel BGA 1744 versus AMD Socket SP3.

Q: What is the difference in their L3 cache sizes?

A: The Intel has 12 MB of shared L3 cache, while the AMD has 256 MB of shared L3 cache—a 21.3x difference in favor of the EPYC.

Where Each One Wins

The AMD EPYC 7643 wins every single benchmark in the head-to-head comparison, so the "where each one wins" section is a one-sided affair. The EPYC's victories span all Cinebench R15, R20, and R23 tests, both multi-core and single-core. This means the EPYC is the clear choice for any workload that relies on raw CPU rendering speed, whether that is multi-threaded video encoding, 3D rendering, or single-threaded simulation tasks that benefit from its higher base and boost clocks. The EPYC's 48 cores and 96 threads, combined with 256 MB of L3 cache and eight-channel DDR4 memory (204.8 GB/s bandwidth), make it a server-grade workhorse. The Intel Core i7-1355U, by contrast, has zero benchmark wins in this comparison, but its profile suggests a different role: a 15 W mobile chip with integrated Iris Xe Graphics, designed for thin-and-light laptops where power efficiency and portability matter more than raw compute. Its 10 cores and 12 threads are respectable for a mobile part, and its 5.00 GHz boost clock is the highest in this comparison, but no benchmark data exists to show it winning any rendering test.

Specification Differences

The two processors differ in nearly every specification category. The Intel has 10 cores and 12 threads; the AMD has 48 cores and 96 threads. The Intel's base clock is 1.70 GHz with a 5.00 GHz boost; the AMD's base is 2.30 GHz with a 3.60 GHz boost. The Intel's TDP is 15 W, while the AMD's is 225 W—a 15x difference in power draw. The Intel uses an Intel BGA 1744 socket, while the AMD uses AMD Socket SP3. The Intel supports DDR4 and DDR5 memory in a dual-channel configuration; the AMD supports only DDR4 but in an eight-channel configuration with a memory bandwidth of 204.8 GB/s. The Intel has no ECC memory support, while the AMD supports ECC. The Intel has integrated graphics (Iris Xe Graphics 96EU), while the AMD has none. The Intel has 8 PCIe Gen 4 lanes, while the AMD has 128 PCIe Gen 4 lanes. The Intel's market segment is mobile; the AMD's is server/workstation. The Intel was released on 2023-01-03, while the AMD was released on 2021-03-14.

Architecture Differences

The architectural divide is stark. The Intel uses Raptor Lake architecture (Raptor Lake-U codename) on a 10 nm process built by Intel, while the AMD uses Zen 3 architecture (Milan codename) on a 7 nm process built by TSMC. The AMD's process node is smaller, and its transistor count is listed as 33,200 million, spread across an 8x 81 mm² die configuration; the Intel's transistor count and die size are not specified in the data. The cache hierarchy differs fundamentally: the Intel has 80 KB of L1 per core, 1.25 MB of L2 per core, and 12 MB of shared L3; the AMD has 64 KB of L1 per core, 512 KB of L2 per core, and 256 MB of shared L3. The AMD's L3 cache is 21.3x larger, a massive advantage for workloads that benefit from large shared caches. The AMD also features ECC memory support and eight-channel memory, while the Intel is limited to dual-channel non-ECC memory. The Intel has integrated graphics, making it a complete system-on-chip for mobile devices; the AMD relies on external GPUs. The Intel's part number is SRMLY, while the AMD's is 100-000000326100-100000326WOF. Both have locked multipliers, so neither supports user overclocking.

The Verdict

The data directs a clear split: the AMD EPYC 7643 is the superior processor for any compute-intensive task, winning all six head-to-head Cinebench benchmarks with margins between 72.2% and 87.2%. Its 48 cores, 96 threads, 256 MB L3 cache, and eight-channel memory make it a server-class part that obliterates the Intel in rendering. The Intel Core i7-1355U, with its 10 cores, 12 threads, and integrated Iris Xe Graphics, is a mobile processor designed for efficiency—its 15 W TDP is a fraction of the AMD's 225 W, and its 5.00 GHz boost clock is the highest of the two, yet it cannot translate that into a single benchmark win. The average benchmark scores are nearly tied (18,730 versus 18,697), but this is a statistical artifact of different benchmark suites, not evidence of comparable performance. Choose the EPYC 7643 if you need maximum multi-threaded throughput and have the power budget and server infrastructure to support it. Choose the Intel i7-1355U if you need a mobile chip with integrated graphics and minimal power draw—but be aware that it loses every rendering test in this comparison. The verdict is not close: the EPYC wins outright, and the Intel's only consolation is its portability and lower power envelope, which are not measured in these benchmarks.