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

The Intel Core i9-9900KS and the Intel Core i9-10900E are both 14nm Intel desktop parts, but they target different priorities. The 9900KS is an unlocked, high-clock-speed specialist from the Coffee Lake generation, while the 10900E is a locked, lower-power Comet Lake chip with more cores. Benchmark data shows a clear, though nuanced, performance hierarchy between the two, with the older part winning every single head-to-head test despite having fewer cores.

Head-to-Head Benchmarks

The most striking result is in Geekbench multicore, where the i9-9900KS posts a score of 9771 against the i9-10900E's 8162. That is a massive 19.7% lead, which is counterintuitive given that the 10900E has 10 cores and 20 threads versus the 9900KS's 8 cores and 16 threads. This suggests that the 9900KS's higher clock speeds and architecture efficiency more than compensate for the two-core deficit in this particular workload.

The single-core Geekbench test tells a similar story, though with a smaller gap. The 9900KS scores 1715, which is 8.9% ahead of the 10900E's 1575. This is a significant margin for a single-threaded test and points directly to the clock speed advantage: the 9900KS boosts to 5.00 GHz, while the 10900E tops out at 4.70 GHz.

The Cinebench suite, which is heavily used for rendering and CPU stress testing, shows a much tighter contest. Across all three versions of Cinebench (R15, R20, and R23), the 9900KS wins by a consistent 2.2% in both single-core and multi-core tests. For example, in Cinebench R23 multi-core, the 9900KS scores 16446 versus 16093 for the 10900E. In single-core, the scores are 2321 and 2272, respectively. The deltas are small enough that real-world differences in rendering times would be barely perceptible, but the data is unambiguous: the 9900KS wins every one of the eight head-to-head comparisons, with a final tally of 8 wins and 0 losses.

Looking at the broader average benchmark score, the 9900KS averages 4738 across all tests, while the 10900E averages 4708. That is a 0.6% difference, which is within the margin of noise for many workloads. Both chips sit at the 59th percentile of all CPUs in the database, meaning they are near-peers in overall performance, even though the 9900KS edges out the 10900E in every direct comparison available.

Architecture Differences

The core architectural divergence is clear: the i9-9900KS uses the Coffee Lake architecture (specifically Coffee Lake-R) on a 180 mm² die, while the i9-10900E uses Comet Lake on a larger 206 mm² die. Both are built on Intel's 14 nm process, and both use the same per-core cache hierarchy: 64 KB of L1 and 256 KB of L2 per core. The key difference in cache is the shared L3, where the 10900E offers 20 MB versus the 9900KS's 16 MB. That extra 4 MB of L3 is likely a factor in helping the 10900E keep pace in Cinebench despite its lower clocks.

The 9900KS is a special edition part with a 127 W TDP, a base clock of 4.00 GHz, and a boost clock of 5.00 GHz. It is multiplier unlocked, meaning it can be overclocked. The 10900E, by contrast, is a locked part with a 65 W TDP, a base clock of 2.80 GHz, and a boost clock of 4.70 GHz. The TDP difference is stark: 127 W versus 65 W. This means the 9900KS is designed to run hot and fast out of the box, while the 10900E is tuned for efficiency and lower power draw.

Socket compatibility is another major split. The 9900KS uses Intel Socket 1151, while the 10900E uses Intel Socket 1200. These are not cross-compatible, so a motherboard purchase is tied to the chip choice. Memory support is similar: both support DDR4 on a dual-channel bus, but the 10900E has a higher theoretical memory bandwidth of 46.9 GB/s versus 42.7 GB/s for the 9900KS. Both offer PCIe Gen 3 with 16 lanes from the CPU, and both feature integrated UHD 630 graphics.

The 9900KS was released on October 27, 2019, with a launch MSRP of $513, and is now end-of-life. The 10900E launched later on April 29, 2020, with a launch MSRP of $488, and remains in active production. The 10900E is part of the Core 10th Gen series, while the 9900KS is a standalone Coffee Lake Refresh part.

The Verdict

From the data, the i9-9900KS is the faster processor in every benchmark tested, but the margin is not uniform. If you are chasing maximum single-thread performance or Geekbench scores, the 9900KS is clearly superior, with an 8.9% single-core and 19.7% multi-core lead in that suite. However, in Cinebench, which is a common proxy for multi-threaded rendering workloads, the 9900KS only wins by 2.2%. That is a small enough gap that the 10900E's lower TDP and active production status might be more attractive for a system that runs long, continuous loads where power draw and heat are concerns.

The 10900E's 65 W TDP is less than half the 9900KS's 127 W, which means it will be far easier to cool in a compact or quiet system. But the 9900KS's 5.00 GHz boost clock is a definitive advantage for latency-sensitive tasks like gaming or lightly-threaded applications, where clock speed often matters more than core count. The 10900E's two extra cores and 20 MB of L3 cache do not translate into a win in any of the eight tests, which suggests that the 9900KS's clock advantage is the dominant factor in these workloads.

For a builder prioritizing raw speed and overclocking flexibility, the i9-9900KS is the pick. For a builder prioritizing efficiency, a locked multiplier, and a current production chip, the i9-10900E is the sensible choice. The data does not support the 10900E as a performance upgrade over the 9900KS; it wins zero tests.

FAQ

Q: Which CPU wins more benchmarks?

A: The Intel Core i9-9900KS wins all 8 head-to-head benchmark comparisons against the i9-10900E, including every Cinebench and Geekbench test.

Q: How much faster is the i9-9900KS in single-core performance?

A: In Geekbench single-core, the i9-9900KS scores 1715 versus 1575 for the i9-10900E, a lead of 8.9%. In Cinebench R23 single-core, the lead is 2.2% (2321 vs 2272).

Q: Does the i9-10900E have more cores?

A: Yes, the i9-10900E has 10 cores and 20 threads, while the i9-9900KS has 8 cores and 16 threads. Despite this core deficit, the i9-9900KS still wins in multi-core tests.

Q: What is the TDP difference between the two?

A: The i9-9900KS has a TDP of 127 W, while the i9-10900E has a TDP of 65 W.

Q: Are these CPUs overclockable?

A: The i9-9900KS has an unlocked multiplier and can be overclocked. The i9-10900E has a locked multiplier and cannot be overclocked.

Q: What sockets do they use?

A: The i9-9900KS uses Intel Socket 1151, and the i9-10900E uses Intel Socket 1200. They are not interchangeable.

Where Each One Wins

The i9-9900KS wins in every measured performance category, but the magnitude of the win varies. Its biggest advantage is in Geekbench multi-core, where it is 19.7% ahead. This suggests that for workloads that are heavily multithreaded but not necessarily optimized for pure core count, the 9900KS's higher clocks and architecture efficiency shine. It also wins single-core tests by a solid margin, making it the better choice for applications that rely on a single thread, such as older games or certain simulation software. The 9900KS's 5.00 GHz boost clock is the highest of the two, and its unlocked multiplier means it can potentially be pushed even higher with manual overclocking.

The i9-10900E does not win any benchmarks, but it has structural advantages that are not captured in these scores. Its 65 W TDP makes it suitable for systems with limited cooling or power budgets. Its 10 cores and 20 threads provide more parallelism for heavily threaded server-style workloads, even if they do not translate into wins in the tested benchmarks. The 10900E also has a larger 20 MB L3 cache and higher memory bandwidth (46.9 GB/s vs 42.7 GB/s), which could benefit specific data-heavy tasks. It is also an active production part, meaning it is still available for new system builds, whereas the 9900KS is end-of-life.

Specification Differences

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

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

| Cores | 8 | 10 |

| Threads | 16 | 20 |

| Base Clock | 4.00 GHz | 2.80 GHz |

| Boost Clock | 5.00 GHz | 4.70 GHz |

| TDP | 127 W | 65 W |

| Socket | Intel Socket 1151 | Intel Socket 1200 |

| Architecture | Coffee Lake | Comet Lake |

| Die Size | 180 mm² | 206 mm² |

| 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 |

| Multiplier Unlocked | Yes | No |

| Production Status | End-of-life | Active |

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

| Launch MSRP | $513 | $488 |