AMD Ryzen 5 7645HX vs AMD Ryzen 7 7800X3D Comparison

Where Each One Wins

The recorded benchmark data splits these two AMD processors into distinct roles. The AMD Ryzen 5 7645HX wins 5 of the 17 head-to-head tests, and every one of those victories is a single-threaded workload. The AMD Ryzen 7 7800X3D wins the remaining 12 tests, and those are dominated by multi-threaded, cache-sensitive, and physics-heavy tasks. This is a clean separation: the mobile chip takes the single-core crown, the desktop chip takes everything that scales with cores and L3 capacity.

For workloads that depend on one core, the Ryzen 5 7645HX is the stronger choice. Its Cinebench R23 single-core score of 1809 beats the Ryzen 7 7800X3D's 1713 by 5.6%. The Geekbench single-core result widens that gap to 9.5%, with 2657 against 2426. PassMark single-thread also goes to the Ryzen 5, 3907 versus 3759, a 3.9% margin. Applications like legacy single-threaded rendering, spreadsheet recalculation, or lightly threaded scripting will favor the mobile part.

The Ryzen 7 7800X3D is the clear winner for throughput. Cinebench R23 multi-core shows 16817 versus 13985, a 16.8% advantage. Geekbench multi-core is even more lopsided: 15610 versus 11586, a 25.8% gap. The data compression test, which often benefits from large cache, goes to the Ryzen 7 by 21.4%, scoring 384669 against 302256. The physics test is the most dramatic difference, with the Ryzen 7 scoring 3522 versus 1497, a 57.5% advantage. Any workload that is heavily threaded, such as video encoding, 3D scene simulation, or batch data processing, will prefer the Ryzen 7 7800X3D.

Architecture Differences

Both processors use the Zen 4 architecture and are fabricated on TSMC's 5 nm process, but they are built for different platforms and purposes. The Ryzen 5 7645HX is part of the Dragon Range codename, uses AMD Socket FL1, and is classified as a mobile processor. The Ryzen 7 7800X3D uses the Raphael codename, AMD Socket AM5, and is a desktop part. Both share the same 71 mm² die size, but the transistor counts differ significantly: the Ryzen 5 has 6,570 million transistors, while the Ryzen 7 has 11,270 million.

The core configurations differ as expected. The Ryzen 5 7645HX has 6 cores and 12 threads, while the Ryzen 7 7800X3D has 8 cores and 16 threads. Base clocks are close, 4.00 GHz versus 4.20 GHz, and both boost to 5.00 GHz. The L1 and L2 caches are identical in structure, 64 KB per core for L1 and 1 MB per core for L2. The L3 cache is where the two diverge sharply: the Ryzen 5 has 32 MB shared, while the Ryzen 7 has 96 MB shared. That 3x L3 difference is the defining architectural distinction, and it shows up in cache-sensitive benchmarks.

Memory support is similar: both support DDR5, dual-channel memory, and 83.2 GB/s bandwidth, and both support ECC memory. PCIe connectivity differs, with the Ryzen 5 offering Gen 5 with 28 lanes (CPU only) versus the Ryzen 7's Gen 5 with 24 lanes (CPU only). Integrated graphics differ in name: the Ryzen 5 uses Radeon 610M, while the Ryzen 7 uses Radeon Graphics. The thermal design power is also very different, with the mobile part rated at 45 W and the desktop part at 120 W. Neither processor has an unlocked multiplier. Both released on the same date and both are still in active production.

Head-to-Head Benchmarks

The most decisive single result is PassMark physics, where the Ryzen 7 7800X3D scores 3522 against the Ryzen 5's 1497, a 57.5% lead. This test is heavily threaded and often sensitive to memory and cache behavior, so the combination of 8 cores and 96 MB L3 explains the magnitude. The next largest gap is in PassMark find prime numbers, where the Ryzen 7 scores 324 versus 178, a 45.1% advantage. That test is integer-heavy and scales with core count.

Geekbench multi-core gives the Ryzen 7 its biggest percentage win among general-purpose benchmarks, 15610 versus 11586, a 25.8% lead. PassMark integer math follows at 25.3%, with 103639 versus 77432. Random string sorting shows a 24.2% gap, 45418 versus 34434. PassMark multithread is 22.8% higher on the Ryzen 7, 34293 versus 26476. Data compression favors the Ryzen 7 by 21.4%, extended instructions by 21.2%, floating point math by 20.2%, and data encryption by 19.9%. Cinebench R15 multi-core is 20.9% higher on the Ryzen 7, 2878.5 versus 2276, and Cinebench R23 multi-core is 16.8% higher, 16817 versus 13985.

The Ryzen 5 7645HX wins are smaller in magnitude. Geekbench single-core is its best result, 2657 versus 2426, a 9.5% lead. Cinebench R23 single-core follows at 5.6%, 1809 versus 1713. PassMark single-thread is 3.9% higher, 3907 versus 3759. Cinebench R15 single-core shows only a 2.7% gap, 289 versus 281.5. The single-core wins are consistent but modest, while the Ryzen 7's multi-core wins are consistently large.

Specification Differences

| Specification | AMD Ryzen 5 7645HX | AMD Ryzen 7 7800X3D |

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

| Cores | 6 | 8 |

| Threads | 12 | 16 |

| Base Clock | 4.00 GHz | 4.20 GHz |

| TDP | 45 W | 120 W |

| Socket | AMD Socket FL1 | AMD Socket AM5 |

| Codename | Dragon Range | Raphael |

| Transistors | 6,570 million | 11,270 million |

| L3 Cache | 32 MB (shared) | 96 MB (shared) |

| PCIe | Gen 5, 28 Lanes (CPU only) | Gen 5, 24 Lanes (CPU only) |

| Integrated Graphics | Radeon 610M | Radeon Graphics |

| Market Segment | Mobile | Desktop |

| Part Number | 100-000000872 | 100-000000910 |

| Launch MSRP | None recorded | $449 |

Both processors share the same 5 nm TSMC process, 71 mm² die size, 64 KB L1 per core, 1 MB L2 per core, 5.00 GHz boost clock, DDR5 memory support, dual-channel memory bus, 83.2 GB/s memory bandwidth, ECC support, locked multiplier, and release date. The Ryzen 7 7800X3D has a launch MSRP of $449; no launch MSRP is recorded for the Ryzen 5 7645HX.

FAQ

Q: Which processor is faster in single-core benchmarks?

A: The AMD Ryzen 5 7645HX wins every recorded single-core test. It leads by 2.7% in Cinebench R15 single-core, 5.6% in Cinebench R23 single-core, 9.5% in Geekbench single-core, and 3.9% in PassMark single-thread.

Q: How much faster is the Ryzen 7 7800X3D in multi-core workloads?

A: The advantage ranges from 16.8% in Cinebench R23 multi-core to 25.8% in Geekbench multi-core. The largest multi-core gap is in PassMark physics, where the Ryzen 7 leads by 57.5%.

Q: What explains the large L3 cache difference?

A: The Ryzen 7 7800X3D has 96 MB of shared L3 cache, while the Ryzen 5 7645HX has 32 MB. This 3x difference in cache capacity directly contributes to the Ryzen 7's wins in data compression, random string sorting, and physics tests.

Q: Are these processors on the same architecture?

A: Yes, both use Zen 4 architecture on TSMC's 5 nm process with a 71 mm² die size. They differ in transistor count, with the Ryzen 7 7800X3D at 11,270 million versus the Ryzen 5 7645HX at 6,570 million.

Q: Do they support the same memory and PCIe features?

A: Both support DDR5, dual-channel memory, 83.2 GB/s bandwidth, and ECC memory. The PCIe configuration differs: the Ryzen 5 7645HX has 28 Gen 5 lanes, while the Ryzen 7 7800X3D has 24 Gen 5 lanes.

Q: Which processor has the higher base clock?

A: The Ryzen 7 7800X3D has a 4.20 GHz base clock, while the Ryzen 5 7645HX has a 4.00 GHz base clock. Both boost to 5.00 GHz.