AMD Ryzen 9 7945HX vs Intel Core Ultra 7 255HX Comparison

The Intel Core Ultra 7 255HX and AMD Ryzen 9 7945HX are two high-end mobile processors that target different strengths. Both are unlocked, 55W TDP parts, but they diverge in architecture, core layout, and benchmark results. The recorded data shows a clear split: AMD wins 8 of 15 head-to-head tests, while Intel takes 7, but the margins vary widely by workload. Intel holds a higher average benchmark score (62,738 vs. 60,099) and a 93rd percentile ranking versus AMD's 92nd, yet the per-test outcomes reveal distinct performance identities.

Head-to-Head Benchmarks

The largest single margin in the comparison belongs to Intel in the Passmark find prime numbers test, where the Core Ultra 7 255HX scores 400 against the Ryzen 9's 284, a 40.8% advantage. Intel also dominates floating point math, posting 160,624 versus 123,390, a 30.2% lead, and physics, with 2,926 against 2,500, a 17% edge. In single-threaded workloads, Intel is consistently ahead: Passmark single thread shows 4,562 vs. 4,040 (12.9% higher), Cinebench R23 single core shows 2,163 vs. 1,940 (11.5% higher), and Cinebench R15 single core shows 327 vs. 308 (6.2% higher).

AMD counters with equally decisive wins in integer-heavy and multi-threaded tasks. The Passmark integer math test shows AMD at 207,524 versus Intel's 127,126, a 38.7% advantage. Data compression favors AMD by 27.2% (707,249 vs. 515,143), random string sorting by 23.4% (81,736 vs. 62,591), and extended instructions by 20.4% (51,834 vs. 41,247). AMD also leads in Passmark multithread (54,548 vs. 48,234, an 11.6% gap), data encryption (42,703 vs. 39,499, 7.5% higher), and both Cinebench multicore tests: R15 multicore 5,289 vs. 4,916 (7.1% ahead) and R23 multicore 33,459 vs. 32,612 (2.5% ahead). The overall win count is close, but the magnitude of AMD's victories in integer math and compression is substantial.

Where Each One Wins

The benchmark results indicate a clear use-case split. AMD's Ryzen 9 7945HX is the stronger choice for workloads that rely on heavy multi-threading, integer arithmetic, and data manipulation. Its 16 cores and 32 threads, combined with a 64 MB shared L3 cache, deliver superior performance in compression, encryption, extended instruction sets, and general multithreaded throughput. The 38.7% lead in integer math and 27.2% lead in data compression are particularly notable for tasks like code compilation, database operations, and file archiving.

Intel's Core Ultra 7 255HX excels in single-threaded responsiveness and floating-point-heavy applications. Its 20 cores and 20 threads, built on a 3 nm process, produce higher scores in Cinebench single-core tests, Passmark single thread, and the physics simulation benchmark. The 30.2% advantage in floating point math makes it a better fit for scientific computing, 3D rendering that relies on FP32/FP64 operations, and certain engineering simulations. The 40.8% lead in prime number finding also points to strength in integer-heavy but latency-sensitive tasks, though AMD's overall integer throughput is higher.

The Verdict

Based strictly on the recorded data, the choice depends on the primary workload. For users who prioritize multi-threaded productivity, data compression, encryption, and integer-heavy processing, the AMD Ryzen 9 7945HX is the stronger option. It wins 8 of the 15 head-to-head tests, including the two Cinebench multicore benchmarks, and its 11.6% lead in Passmark multithread confirms its advantage in parallel workloads. The 38.7% margin in integer math is the largest single win in the comparison.

For users who need top single-thread performance, floating point capability, or physics simulation, the Intel Core Ultra 7 255HX is the better pick. It wins all single-core tests, with a 12.9% lead in Passmark single thread and an 11.5% lead in Cinebench R23 single core. Its 30.2% advantage in floating point math and 17% edge in physics make it a compelling choice for scientific and engineering applications. Additionally, Intel's higher average benchmark score (62,738 vs. 60,099) and 93rd percentile ranking suggest that, across a broad mix of workloads, it edges out AMD in overall performance, even though AMD wins more individual tests.

FAQ

Q: Which CPU has higher single-core performance?

A: The Intel Core Ultra 7 255HX wins in every single-core test. It scores 2,163 in Cinebench R23 single core versus AMD's 1,940 (11.5% higher) and 4,562 in Passmark single thread versus 4,040 (12.9% higher).

Q: Which CPU is better for multi-threaded workloads?

A: The AMD Ryzen 9 7945HX leads in most multi-threaded tests, including Cinebench R23 multicore (33,459 vs. 32,612, 2.5% ahead) and Passmark multithread (54,548 vs. 48,234, 11.6% ahead). However, Intel wins in floating point math and prime number finding.

Q: What are the core and thread counts?

A: The Intel Core Ultra 7 255HX has 20 cores and 20 threads. The AMD Ryzen 9 7945HX has 16 cores and 32 threads.

Q: Which CPU has a larger L3 cache?

A: The AMD Ryzen 9 7945HX has 64 MB of shared L3 cache, while the Intel Core Ultra 7 255HX has 30 MB.

Q: Which CPU supports ECC memory?

A: The AMD Ryzen 9 7945HX supports ECC memory; the Intel Core Ultra 7 255HX does not.

Q: What is the memory bandwidth difference?

A: The Intel Core Ultra 7 255HX has a memory bandwidth of 102.4 GB/s, while the AMD Ryzen 9 7945HX has 83.2 GB/s.

Architecture Differences

The two processors are built on fundamentally different architectures. The Intel Core Ultra 7 255HX uses the Arrow Lake-HX design, fabricated on a 3 nm process at TSMC, with 17,800 million transistors on a 243 mm² die. It features 20 cores and 20 threads, with 192 KB of L1 cache per core, 3 MB of L2 per core, and 30 MB of shared L3. The AMD Ryzen 9 7945HX uses the Zen 4 Dragon Range architecture, on a 5 nm process, with 13,140 million transistors across two 71 mm² dies (142 mm² total). It has 16 cores and 32 threads, with 64 KB of L1 per core, 1 MB of L2 per core, and 64 MB of shared L3.

Memory support differs as well. Both support DDR5 in dual-channel mode, but Intel's bandwidth is 102.4 GB/s versus AMD's 83.2 GB/s. AMD includes ECC support, while Intel does not. PCIe connectivity also varies: Intel provides Gen 5 with 20 CPU lanes, while AMD offers Gen 5 with 28 lanes. Integrated graphics are present on both, with Intel's Arc Xe-LPG 64EU and AMD's Radeon 610M, though no benchmark data is available for either. Both processors have unlocked multipliers and a 55W TDP. The Intel part was released on January 12, 2025, while the AMD part launched on January 3, 2023. These architectural differences explain the performance split: AMD's larger L3 cache and higher thread count drive its multi-threaded wins, while Intel's newer 3 nm process and higher per-core cache contribute to its single-thread and floating-point advantages.