Intel Core i9-10900 vs Intel Core i9-9900KS Comparison

FAQ

Q: Which processor has the higher boost clock speed?

A: The Intel Core i9-10900 has a boost clock of 5.20 GHz, which is higher than the Intel Core i9-9900KS's 5.00 GHz.

Q: How do the two chips compare in core and thread counts?

A: The Intel Core i9-10900 has 10 cores and 20 threads, while the Intel Core i9-9900KS has 8 cores and 16 threads.

Q: Which CPU has a larger L3 cache?

A: The Intel Core i9-10900 has 20 MB of shared L3 cache, while the Intel Core i9-9900KS has 16 MB of shared L3 cache.

Q: Which processor won more head-to-head benchmark comparisons?

A: The Intel Core i9-9900KS won 12 of the 14 head-to-head benchmark tests, while the Intel Core i9-10900 won 2.

Q: What is the socket difference between these two processors?

A: The Intel Core i9-9900KS uses Intel Socket 1151, while the Intel Core i9-10900 uses Intel Socket 1200.

Q: Are both processors unlocked for overclocking?

A: No, the Intel Core i9-9900KS has an unlocked multiplier, while the Intel Core i9-10900 has a locked multiplier.

Architecture Differences

The two processors belong to different Intel generations, despite sharing the same 14 nm process node and Intel as both manufacturer and foundry. The Intel Core i9-9900KS is built on the Coffee Lake architecture, specifically the Coffee Lake-R codename, and belongs to the Core i9 (Coffee Lake Refresh) generation. The Intel Core i9-10900 is built on the Comet Lake architecture with the Comet Lake codename, belonging to the Core i9 (Comet Lake) generation.

The core configuration differs significantly. The 9900KS provides 8 cores and 16 threads, while the 10900 offers 10 cores and 20 threads. Both chips use 64 KB of L1 cache per core and 256 KB of L2 cache per core, but the shared L3 cache differs: the 9900KS has 16 MB while the 10900 has 20 MB.

The memory architecture shows a modest advancement in the newer chip. Both support DDR4 memory with a dual-channel bus, but the 10900 has a memory bandwidth of 46.9 GB/s compared to the 9900KS's 42.7 GB/s. Neither processor supports ECC memory, and both provide PCIe Gen 3 with 16 lanes from the CPU.

The integrated graphics differ slightly in naming: the 9900KS includes UHD 630, while the 10900 includes UHD Graphics 630. Both are desktop market segment parts, and both are marked as end-of-life in the database.

The die size is recorded for the 9900KS at 180 mm², while no die size is listed for the 10900. The base clock shows a notable split: the 9900KS runs at 4.00 GHz base, while the 10900 runs at a lower 2.80 GHz base, but boosts higher to 5.20 GHz versus the 9900KS's 5.00 GHz.

The power envelope differs substantially. The 9900KS has a TDP of 127, while the 10900 has a TDP of 65, despite the latter having more cores. The socket change from Intel Socket 1151 to Intel Socket 1200 means the two are not directly interchangeable on the same motherboard.

Where Each One Wins

The Intel Core i9-9900KS dominates in lightly threaded and mid-range threaded workloads. In the head-to-head data, it wins all 3DMark tests through 8 threads, including a 9.7% advantage in 3DMark 8-thread performance. It also wins every Cinebench test, both single-core and multi-core, across R15, R20, and R23 versions. The Geekbench results show its largest margin: 13.8% in multi-core and 3.9% in single-core.

The Intel Core i9-10900 wins specifically where thread count matters most. Its 10 cores and 20 threads give it a clear edge in the 3DMark max-threads test, where it scores 8083 against the 9900KS's 7360, an 8.9% advantage. It also narrowly wins the 3DMark 16-thread test by 0.2%, the only other head-to-head test it takes.

The pattern is consistent: the 9900KS is the stronger choice for workloads that use up to 8 threads or rely on high single-thread performance, while the 10900 pulls ahead when all available threads are engaged. The 9900KS's higher base clock of 4.00 GHz helps it in shorter, lower-thread tasks, while the 10900's two extra cores and five extra threads show up only in the most heavily threaded scenarios.

Specification Differences

| Specification | Intel Core i9-9900KS | Intel Core i9-10900 |

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

| Cores | 8 | 10 |

| Threads | 16 | 20 |

| Base Clock | 4.00 GHz | 2.80 GHz |

| Boost Clock | 5.00 GHz | 5.20 GHz |

| TDP | 127 | 65 |

| Socket | Intel Socket 1151 | Intel Socket 1200 |

| Architecture | Coffee Lake | Comet Lake |

| Codename | Coffee Lake-R | Comet Lake |

| Generation | Core i9 (Coffee Lake Refresh) | Core i9 (Comet Lake) |

| Die Size | 180 mm² | Not listed |

| L3 Cache | 16 MB (shared) | 20 MB (shared) |

| Memory Bandwidth | 42.7 GB/s | 46.9 GB/s |

| Integrated Graphics | UHD 630 | UHD Graphics 630 |

| Release Date | 2019-10-27 | 2020-04-29 |

| Launch MSRP | $513 | $483 |

| Multiplier Unlocked | Yes | No |

| Part Number | SRG1Q | SRH8Z |

Both processors use the same 14 nm process node, same L1 and L2 cache layout, same dual-channel DDR4 memory support, same PCIe Gen 3 with 16 lanes, and neither supports ECC memory. The 9900KS is the only one with an unlocked multiplier.

Head-to-Head Benchmarks

The benchmark data shows a clear split between the two processors. The Intel Core i9-9900KS wins 12 of 14 tests, while the Intel Core i9-10900 wins 2.

The largest win for the 9900KS comes in Geekbench multi-core, where it scores 9771 against the 10900's 8585, a 13.8% advantage. This is notable because the 10900 has more cores and threads, yet the 9900KS still comes out ahead in this workload. The Geekbench single-core test also favors the 9900KS by 3.9%, with scores of 1715 versus 1651.

The 3DMark suite shows a thread-dependent pattern. The 9900KS wins the 2-thread test by 4.5% (1670 versus 1598), the 4-thread test by 7.3% (3276 versus 3052), and the 8-thread test by 9.7% (5787 versus 5276). It also wins the single-thread test by 3.2% (841 versus 815). The 10900 takes the max-threads test by 8.9% (8083 versus 7360) and the 16-thread test by a marginal 0.2% (7391 versus 7376).

The Cinebench results are consistently close but always favor the 9900KS. In Cinebench R15, the 9900KS wins multi-core by 1.4% (1657 versus 1634) and single-core by 1.3% (233 versus 230). The R20 results show the same 1.4% margin in both multi-core (6907 versus 6811) and single-core (974 versus 961). Cinebench R23 repeats the pattern with a 1.4% win in both multi-core (16446 versus 16219) and single-core (2321 versus 2289).

The overall average benchmark scores reflect this mixed picture. The 9900KS has an average benchmark score of 4738, placing it in the 59th percentile of all CPUs. The 10900 has an average of 4614, placing it in the 58th percentile. The nearest rivals for the 9900KS include the Intel Core i7-6950X at 4734 (0.1% difference) and the AMD EPYC 7252 at 4772 (-0.7% difference). The nearest rivals for the 10900 include the Intel Core i9-9900KF at 4652 (-0.8% difference) and the Intel Xeon W-2145 at 4576 (0.8% difference).

The Verdict

The data indicates that the Intel Core i9-9900KS is the stronger overall performer in the majority of recorded benchmarks, winning 12 of 14 head-to-head tests. Its wins span both single-threaded and multi-threaded workloads, and it holds a particularly large 13.8% advantage in Geekbench multi-core. The 9900KS also offers an unlocked multiplier, which the 10900 lacks, making it the more flexible choice for users who want to adjust clock speeds.

The Intel Core i9-10900 is the better choice only in the most heavily threaded scenarios. Its 10 cores and 20 threads allow it to win the 3DMark max-threads test by 8.9% and the 16-thread test by 0.2%. For workloads that scale beyond 8 threads and use every available thread, the 10900's extra cores provide a measurable benefit. It also has a higher boost clock (5.20 GHz versus 5.00 GHz) and more L3 cache (20 MB versus 16 MB).

The 9900KS edges out the 10900 in every Cinebench test, but the margins are slim at 1.4% or less. The 10900's lower TDP of 65 versus 127 may appeal to system builders concerned with power draw, though the database does not provide direct thermal or power consumption measurements.

For users prioritizing single-thread performance, moderate thread counts, or overclocking capability, the Intel Core i9-9900KS is the data-backed pick. For users running heavily threaded applications that saturate 10 cores or more, the Intel Core i9-10900 is the appropriate selection. The 10900 also has a lower launch MSRP of $483 compared to the 9900KS's $513, though both parts are now end-of-life in the database.