AMD Ryzen 5 8640HS vs Intel Core i9-11900KF Comparison

The Intel Core i9-11900KF and AMD Ryzen 5 8640HS are two very different processors that end up in a similar performance bracket, but the data shows a clear split: the Intel part wins 14 of 17 head-to-head benchmarks, often by massive margins, while the AMD chip takes the remaining three with only narrow victories. The i9-11900KF is a desktop-class 8-core part aimed at maximum throughput, while the 8640HS is a mobile 6-core part that trades performance for efficiency, yet both land at the 78th percentile among all CPUs.

FAQ

Q: Which processor has the higher average benchmark score?

A: The Intel Core i9-11900KF has an average benchmark score of 26212, while the AMD Ryzen 5 8640HS scores 26106. The difference is only 0.4%, with the Intel part listed as a nearest rival to the AMD chip with a deltaPct of 0.4.

Q: How do the two compare in single-threaded performance?

A: The results are nearly tied. The AMD Ryzen 5 8640HS wins the PassMark single-thread test with a score of 3584 versus 3527 for the Intel part, a delta of -1.6%. However, the Intel i9-11900KF wins Cinebench R23 single-core by a huge 71.9%, scoring 2941 versus 1711.

Q: Which chip has more cores and threads?

A: The Intel Core i9-11900KF has 8 cores and 16 threads, while the AMD Ryzen 5 8640HS has 6 cores and 12 threads. The Intel part also has a higher boost clock of 5.30 GHz compared to 4.90 GHz on the AMD.

Q: What is the biggest performance gap between the two chips?

A: The largest difference is in Cinebench R23 multi-core, where the Intel Core i9-11900KF scores 20838 versus 11486 for the AMD Ryzen 5 8640HS. That is an 81.4% lead for the Intel processor.

Q: Are there any benchmarks where the AMD Ryzen 5 8640HS wins?

A: Yes, the AMD chip wins three head-to-head tests: PassMark find prime numbers (70 vs 66), PassMark single-thread (3584 vs 3527), and the duplicate PassMark singlethread test (3584 vs 3527). All three wins are by single-digit percentage margins.

Q: What are the production statuses of these two CPUs?

A: The Intel Core i9-11900KF is listed as end-of-life, while the AMD Ryzen 5 8640HS is marked as active production. The Intel part was released on 2021-03-15, and the AMD part on 2023-12-05.

Architecture Differences

The architectural gap between these two chips is generational. The Intel Core i9-11900KF uses the Rocket Lake architecture on a 14 nm process node manufactured by Intel, with a die size of 276 mm². The AMD Ryzen 5 8640HS uses Zen 4 under the Hawk Point codename, built on a 4 nm process by TSMC, with a die size of 178 mm² and 25,000 million transistors.

The core configurations differ significantly. Intel provides 8 cores and 16 threads, while AMD offers 6 cores and 12 threads. The cache layouts also diverge: Intel has 80 KB of L1 per core and 512 KB of L2 per core, whereas AMD has 64 KB of L1 per core and a larger 1 MB of L2 per core. Both share 16 MB of L3 cache. The base clocks are identical at 3.50 GHz, but Intel boosts higher to 5.30 GHz versus 4.90 GHz on the AMD.

The Intel part is a desktop chip on Socket 1200 with a 125 W TDP and supports DDR4 memory, while the AMD chip is a mobile part on Socket FP8 with a 28 W TDP and supports DDR5. The AMD chip includes integrated Radeon 760M graphics, whereas the Intel part has no integrated graphics listed. Both support Gen 4 PCIe with 20 CPU lanes, but the memory bandwidth differs substantially: Intel offers 51.2 GB/s, AMD offers 89.6 GB/s.

The Verdict

For anyone building a desktop system where raw compute is the priority, the Intel Core i9-11900KF is the unequivocal choice based on benchmark data. It wins 14 of 17 head-to-head tests, and its multi-core victories are not marginal — they are decisive. The 81.4% lead in Cinebench R23 multi-core and the 46.8% lead in Geekbench multi-core demonstrate that the Intel chip is in a different performance class for threaded workloads, despite having only two more cores.

The AMD Ryzen 5 8640HS, however, is the only sensible pick for mobile or low-power systems. It is an active production mobile chip with a 28 W TDP versus 125 W on the Intel part, and it includes integrated graphics. The data shows it wins only three tests, but those are single-thread and prime-number workloads where it edges ahead by 1.6% and 5.7% respectively. For a laptop processor, these narrow wins are irrelevant compared to the massive power and thermal advantages it holds.

The average benchmark scores are nearly identical at 26212 for Intel and 26106 for AMD, which explains why they appear as nearest rivals to each other. But that average hides the distribution: the Intel chip wins big in multi-core and loses small in a few single-thread tests. The verdict is clear — the Intel i9-11900KF is for desktop performance, the AMD Ryzen 5 8640HS is for mobile efficiency.

Specification Differences

The two processors differ in nearly every fundamental specification. The Intel Core i9-11900KF has 8 cores and 16 threads, while the AMD Ryzen 5 8640HS has 6 cores and 12 threads. Both have a base clock of 3.50 GHz, but the Intel chip boosts to 5.30 GHz versus 4.90 GHz on the AMD. The TDP is drastically different: 125 W for Intel versus 28 W for AMD.

The process node and foundry are also different: Intel uses 14 nm from its own foundry, while AMD uses 4 nm from TSMC. The die sizes are 276 mm² for Intel and 178 mm² for AMD, with AMD listing 25,000 million transistors. Cache configurations differ in L1 and L2: Intel has 80 KB and 512 KB per core respectively, while AMD has 64 KB and 1 MB per core. Both share 16 MB of L3.

Memory support differs by generation: Intel supports DDR4, AMD supports DDR5. The memory bandwidth is 51.2 GB/s on Intel versus 89.6 GB/s on AMD. Neither supports ECC. The Intel chip is on Socket 1200 with an unlocked multiplier, while the AMD chip is on Socket FP8 with a locked multiplier. Intel has no integrated graphics, AMD includes Radeon 760M. The Intel part is desktop and end-of-life, the AMD part is mobile and active.

Head-to-Head Benchmarks

The Intel Core i9-11900KF dominates the benchmark suite, but the AMD Ryzen 5 8640HS has a few bright spots. Starting with the biggest Intel wins, Cinebench R23 multi-core shows a score of 20838 for Intel versus 11486 for AMD, an 81.4% delta. Cinebench R23 single-core is nearly as lopsided: Intel scores 2941 versus 1711, a 71.9% lead. Geekbench multi-core gives Intel 10953 versus 7461, a 46.8% advantage.

The data compression test follows the same trend, with Intel scoring 325688 versus 226544, a 43.8% lead. Extended instructions show Intel at 22703 versus 15855, a 43.2% delta. Random string sorting goes to Intel with 37383 versus 27316, a 36.9% gap. Floating point math favors Intel at 52640 versus 39725, a 32.5% lead. Integer math shows Intel at 89023 versus 68173, a 30.6% edge. PassMark multithread gives Intel 24708 versus 19889, a 24.2% win.

The smaller Intel wins include Geekbench single-core at 2062 versus 1778 (16%), data encryption at 15623 versus 13551 (15.3%), Cinebench R15 multi-core at 2100 versus 1845 (13.8%), Cinebench R15 single-core at 296 versus 268 (10.4%), and PassMark physics at 1034 versus 970 (6.6%). The AMD wins are narrow: find prime numbers at 70 versus 66 (-5.7%), and single-thread tests at 3584 versus 3527 (-1.6%).

Where Each One Wins

The Intel Core i9-11900KF wins in every multi-threaded workload that requires sustained throughput. The 81.4% lead in Cinebench R23 multi-core is the defining statistic, but the 46.8% Geekbench multi-core win and the 24.2% PassMark multithread win confirm that this is not a fluke. For data compression, extended instructions, floating point, and integer math, the Intel part leads by 30% to 44%. This is the chip for rendering, compiling, and heavy computation.

The AMD Ryzen 5 8640HS wins only three tests, and all are narrow. The PassMark single-thread score of 3584 versus 3527 is a 1.6% margin, and the find prime numbers test at 70 versus 66 is a 5.7% edge. These wins suggest a slight advantage in specific scalar workloads, but the margins are too small to matter in practice. The AMD chip's real wins are not in the benchmark scores — they are in the fact that it is a 28 W mobile part with integrated graphics, which makes it viable for laptops where the Intel chip cannot exist.