AMD Ryzen 5 PRO 7645 vs Intel Core Ultra 7 155H Comparison

# Head-to-Head Benchmarks

The benchmark data paints a clear picture: the AMD Ryzen 5 PRO 7645 dominates the Intel Core Ultra 7 155H in the majority of tests, winning 13 of 17 head-to-head comparisons. However, the Intel chip secures decisive victories in specific math-heavy workloads that reveal its architectural strengths.

The single most dramatic gap appears in Cinebench R23 multi-core, where the AMD Ryzen 5 PRO 7645 scores 21,710 against Intel's 15,028 — a 30.8% advantage. This is not a marginal difference; it signals that the Zen 4 architecture sustains high throughput across all six cores under sustained load. The single-core R23 result is even more lopsided: AMD posts 3,065 versus Intel's 1,743, a 43.1% deficit for the Core Ultra 7 155H. That single-core deficit is the largest percentage gap in the entire benchmark suite.

Cinebench R20 tells a slightly different story. The AMD chip wins multi-core with 9,118 versus 8,754 (4% ahead) and single-core with 1,287 versus 1,235 (4% ahead). The margins shrink considerably compared to R23, suggesting that the Intel chip's performance scales differently across Cinebench versions. In R15 multi-core, Intel actually takes the win: 2,450 versus 2,188, a 12% advantage. This inversion — Intel winning the older R15 test while losing R20 and R23 — indicates that the Core Ultra 7 155H's 16-core/22-thread configuration excels in shorter, less cache-sensitive workloads.

The PassMark suite reveals where each processor's architecture shines. Intel's Core Ultra 7 155H wins floating-point math decisively: 63,703 versus 45,202, a 40.9% advantage. This is the largest Intel win in any test and points to the Meteor Lake's integrated Arc Xe-LPG graphics and vector processing capabilities contributing to FP throughput. Intel also takes integer math at 86,870 versus 74,782 (16.2% ahead) and physics at 1,727 versus 1,598 (8.1% ahead).

AMD counters across the rest of PassMark. Extended instructions favor AMD heavily: 21,813 versus 16,456, a 24.6% gap. Prime number finding shows AMD at 198 versus Intel's 113, a 42.9% advantage — nearly as large as the R23 single-core gap. Data compression goes to AMD 286,298 versus 277,353 (3.1% ahead), and data encryption follows at 16,657 versus 16,358 (1.8% ahead).

Random string sorting favors AMD at 34,557 versus 31,990 (7.4% ahead), while the PassMark multi-thread score is close: AMD 25,489 versus Intel 24,873 (2.4% ahead). Single-thread performance also goes to AMD at 3,652 versus 3,468 (5% ahead). The overall average benchmark scores are nearly identical — Intel at 32,697 and AMD at 32,446 — which explains why both processors sit at the 83rd percentile among all CPUs.

# The Verdict

The data supports a straightforward conclusion: the AMD Ryzen 5 PRO 7645 is the stronger all-around processor for most workloads. Its 13 wins versus Intel's 4 wins is not close, and the magnitude of its victories in Cinebench R23 multi-core (30.8%) and single-core (43.1%) are decisive. The AMD chip also delivers higher single-thread performance in every Cinebench and PassMark single-thread test, which is critical for everyday responsiveness and lightly-threaded applications.

The Intel Core Ultra 7 155H is not without merit. Its 40.9% win in floating-point math and 16.2% win in integer math make it the clear choice for compute-heavy scientific or engineering workloads that rely on those specific operations. It also wins the older Cinebench R15 multi-core test and the PassMark physics test, indicating competence in certain legacy or physics-simulation scenarios.

The average benchmark scores are nearly dead even — Intel at 32,697, AMD at 32,446 — meaning the two chips are peers in overall aggregate performance. But the distribution of wins matters. AMD's victories are concentrated in the most demanding modern benchmarks (R23) and in extended instruction throughput, while Intel's wins are in math primitives that may not translate to real-world application speedups.

For a buyer choosing between these two, the AMD Ryzen 5 PRO 7645 offers superior multi-core rendering performance, better single-thread speed, and wins in data compression, encryption, and string sorting. The Intel chip only makes sense if floating-point math or integer math performance is the absolute priority, or if the workload is specifically optimized for Meteor Lake's architecture.

# Where Each One Wins

AMD Ryzen 5 PRO 7645 wins in: Rendering and content creation, evidenced by the 30.8% lead in Cinebench R23 multi-core and 43.1% lead in single-core. Data-heavy operations benefit from its 3.1% compression win and 1.8% encryption win. Extended instruction workloads (SIMD, vectorized code) run 24.6% faster. Prime-number finding, a proxy for integer-heavy algorithms, is 42.9% faster. Random string sorting is 7.4% faster, and general multi-thread and single-thread PassMark scores are 2.4% and 5% faster respectively.

Intel Core Ultra 7 155H wins in: Floating-point math by a massive 40.9% margin, making it suitable for scientific simulations, financial modeling, or any workload dominated by FPU operations. Integer math is 16.2% faster, aiding in cryptography or complex integer calculations. Physics simulation is 8.1% faster, and the Cinebench R15 multi-core test shows a 12% advantage, suggesting it handles short-burst multi-threaded tasks well.

The use-case split is clear: choose AMD for rendering, data processing, and general productivity; choose Intel for math-intensive computation where floating-point and integer throughput are the bottlenecks.

# FAQ

Q: Which processor has better multi-core performance?

A: The AMD Ryzen 5 PRO 7645 wins Cinebench R20 multi-core (9,118 vs 8,754) and R23 multi-core (21,710 vs 15,028), but loses Cinebench R15 multi-core (2,188 vs 2,450). PassMark multi-thread slightly favors AMD at 25,489 versus 24,873.

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

A: AMD leads in every single-core test. The largest gap is Cinebench R23 single-core at 3,065 versus 1,743, a 43.1% advantage. PassMark single-thread shows AMD ahead 3,652 versus 3,468 (5%).

Q: Which CPU is better for math-heavy workloads?

A: The Intel Core Ultra 7 155H wins floating-point math decisively at 63,703 versus 45,202 (40.9% ahead) and integer math at 86,870 versus 74,782 (16.2% ahead). AMD wins extended instructions at 21,813 versus 16,456 (24.6% ahead).

Q: What are the core and thread counts?

A: The Intel Core Ultra 7 155H has 16 cores and 22 threads. The AMD Ryzen 5 PRO 7645 has 6 cores and 12 threads.

Q: How do the two compare in overall average benchmark score?

A: They are nearly identical. Intel scores 32,697 average and AMD scores 32,446 average. Both are at the 83rd percentile among all CPUs.

Q: Which processor has more L3 cache?

A: The AMD Ryzen 5 PRO 7645 has 32 MB of shared L3 cache, while the Intel Core Ultra 7 155H has 24 MB of shared L3 cache.

# Architecture Differences

The two processors come from fundamentally different design philosophies. The Intel Core Ultra 7 155H is built on Meteor Lake architecture using Intel's 7 nm process node, fabricated by Intel itself. It integrates Arc Xe-LPG 128EU graphics. The AMD Ryzen 5 PRO 7645 uses Zen 4 architecture (codenamed Raphael) on a 5 nm process from TSMC, with 6,570 million transistors on a 71 mm² die.

Cache hierarchies differ substantially. Intel allocates 112 KB L1 per core and 2 MB L2 per core, while AMD uses 64 KB L1 per core and 1 MB L2 per core. The shared L3 cache favors AMD at 32 MB versus Intel's 24 MB. This larger L3 cache likely contributes to AMD's wins in data compression and extended instructions.

Memory support shows both support DDR5, but Intel's memory support is noted as "depends on motherboard" while AMD's is simply DDR5. Memory bandwidth slightly favors Intel at 89.6 GB/s versus AMD's 83.2 GB/s. ECC memory support is exclusive to AMD, which is significant for workstation reliability. PCIe lanes differ: AMD offers Gen 5 with 24 lanes (CPU only) versus Intel's Gen 5 with 8 lanes (CPU only).

The processors are built for different market segments: Intel targets mobile with a 28 TDP and an integrated GPU, while AMD is classified as server/workstation with a 65 TDP. Both use different sockets — Intel BGA 2049 versus AMD Socket AM5 — and neither has an unlocked multiplier.

# Specification Differences

| Specification | Intel Core Ultra 7 155H | AMD Ryzen 5 PRO 7645 |

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

| Cores | 16 | 6 |

| Threads | 22 | 12 |

| Boost Clock | 4.80 GHz | 5.10 GHz |

| TDP | 28 W | 65 W |

| Socket | Intel BGA 2049 | AMD Socket AM5 |

| Process Node | 7 nm | 5 nm |

| Foundry | Intel | TSMC |

| L1 Cache | 112 KB (per core) | 64 KB (per core) |

| L2 Cache | 2 MB (per core) | 1 MB (per core) |

| L3 Cache | 24 MB (shared) | 32 MB (shared) |

| Memory Bandwidth | 89.6 GB/s | 83.2 GB/s |

| ECC Memory | No | Yes |

| PCIe | Gen 5, 8 Lanes (CPU only) | Gen 5, 24 Lanes (CPU only) |

| Integrated Graphics | Arc Xe-LPG 128EU | Radeon Graphics |

| Market Segment | Mobile | Server/Workstation |

| Release Date | 2023-12-13 | 2023-06-12 |

| Transistor Count | Not listed | 6,570 million |

| Die Size | Not listed | 71 mm² |

The base clock is identical at 3.80 GHz for both, but AMD boosts higher to 5.10 GHz versus Intel's 4.80 GHz. Intel has a higher TDP efficiency at 28 W versus AMD's 65 W, though AMD compensates with more PCIe lanes and ECC support. Both use dual-channel memory buses, and neither processor has an unlocked multiplier.