CPU Comparison

The Intel Core i9-12900E and Intel Atom x7405C occupy opposite ends of Intel’s performance spectrum, yet both are listed as active production parts. The benchmark database shows a stark divide: the Core i9-12900E wins every single head-to-head benchmark, while the Atom x7405C counters with a dramatically lower power envelope and a distinct architectural focus. This analysis breaks down where each processor excels and what the numbers reveal about their intended roles.

Head-to-Head Benchmarks

The data is unambiguous. Across all six shared benchmark tests, the Intel Core i9-12900E delivers a performance advantage that ranges from 430.5% to 438.7%. The largest single-core margin comes in Cinebench R15, where the i9-12900E scores 334 against the Atom’s 62, a delta of 438.7%. The smallest margin, though still overwhelming, is in Cinebench R23 multi-core, where the i9-12900E posts 23,529 versus the Atom’s 4,435, a 430.5% lead.

Multi-core results follow the same pattern. In Cinebench R20 multi-core, the i9-12900E scores 9,882, which is 430.7% ahead of the Atom’s 1,862. Cinebench R15 multi-core shows 2,371 versus 446, a 431.6% difference. The single-core deltas are consistently higher than multi-core deltas, suggesting the i9-12900E’s architecture scales better on lightly threaded workloads relative to the Atom. The i9-12900E’s Cinebench R23 single-core score of 3,321 is 430.5% above the Atom’s 626, mirroring the multi-core gap almost exactly.

Notably, the Atom x7405C has additional PassMark benchmarks not shared with the i9-12900E, including data compression (56,317), data encryption (4,004), and physics (460). These results cannot be directly compared, but they show the Atom has measurable throughput in specific integer and encryption tasks. However, in the six tests where both CPUs are measured, the i9-12900E is never challenged. The wins tally is 6-0, with no benchmark where the Atom comes within an order of magnitude.

FAQ

Q: Which CPU has a higher average benchmark score?

A: The Intel Core i9-12900E has an average benchmark score of 6,611, while the Intel Atom x7405C averages 6,568. The difference is only 0.7%, despite the i9-12900E winning every shared test. This is because the Atom’s PassMark results, which are not shared with the i9-12900E, pull its average upward.

Q: How do the two CPUs compare in Cinebench R23 multi-core?

A: The i9-12900E scores 23,529, which is 430.5% higher than the Atom’s 4,435. This is the largest absolute gap in the shared benchmark set, reflecting the i9-12900E’s 16 cores and 24 threads versus the Atom’s 4 cores and 4 threads.

Q: What is the single-core performance difference?

A: In Cinebench R23 single-core, the i9-12900E scores 3,321 versus the Atom’s 626, a 430.5% lead. In Cinebench R15 single-core, the gap is 438.7% (334 vs 62), indicating the i9-12900E has a stronger per-thread advantage at lower thread counts.

Q: Does the Atom x7405C have any benchmark where it wins?

A: No. In the six head-to-head benchmarks listed, the Atom x7405C has zero wins. Its available PassMark scores, such as integer math (14,669) and floating point math (9,063), are not compared against the i9-12900E in this dataset.

Q: How does the power efficiency compare?

A: The Atom x7405C has a TDP of 12 watts, while the i9-12900E has a TDP of 65 watts. The Atom’s TDP is roughly one-fifth of the i9-12900E’s, though the performance per watt cannot be calculated from the provided data since the i9-12900E lacks corresponding low-power benchmarks.

Q: Are both CPUs in the same market segment?

A: No. The i9-12900E is listed as a Desktop processor, while the Atom x7405C is listed as a Mobile processor. This aligns with their socket types: the i9-12900E uses Intel Socket 1700, and the Atom uses Intel BGA 1264.

Architecture Differences

The two processors are built on the same 10 nm process node and both use Intel as the foundry, but their architectures diverge completely. The i9-12900E is based on Alder Lake-S, part of the Core 12th Gen series. It uses a hybrid design with 16 cores and 24 threads, which implies a combination of performance and efficiency cores, though the exact split is not specified. The Atom x7405C is based on Amston Lake, categorized under the Atom (Gracemont) generation. This is a simpler, unified core design with 4 cores and 4 threads.

Cache hierarchies differ significantly. The i9-12900E has 80 KB of L1 cache per core and 1.25 MB of L2 cache per core, with a 30 MB shared L3 cache. The Atom x7405C has 96 KB of L1 per core but only 2 MB of shared L2, plus 6 MB of shared L3. The i9-12900E’s larger L3 cache (30 MB vs 6 MB) is a key factor in its multi-threaded dominance, while the Atom’s higher per-core L1 might help with specific low-latency tasks.

Memory architecture also separates the two. The i9-12900E supports dual-channel memory, whereas the Atom x7405C is single-channel. The Atom does list a memory bandwidth of 38.4 GB/s, which is not provided for the i9-12900E. PCIe support is another clear split: the i9-12900E offers Gen 5 with 20 lanes (CPU only), while the Atom offers Gen 3 with 9 lanes (CPU only). The i9-12900E includes integrated UHD Graphics 770; the Atom has no integrated graphics.

Specification Differences

The most obvious difference is core count: 16 cores and 24 threads for the i9-12900E, versus 4 cores and 4 threads for the Atom x7405C. Base clocks are 2.30 GHz for the i9-12900E and 1.70 GHz for the Atom, with boost clocks of 5.00 GHz and 3.40 GHz, respectively. The i9-12900E has a 65 W TDP, while the Atom sits at 12 W.

Socket types differ entirely: Intel Socket 1700 for the i9-12900E and Intel BGA 1264 for the Atom. The i9-12900E has a die size of 215 mm², while the Atom’s die size is not listed. L3 cache is 30 MB shared on the i9-12900E versus 6 MB shared on the Atom. The i9-12900E uses DDR4 and DDR5 memory, as does the Atom, but the memory bus is dual-channel versus single-channel. PCIe generation and lane count differ (Gen 5, 20 lanes vs Gen 3, 9 lanes). Integrated graphics are present on the i9-12900E (UHD Graphics 770) but listed as N/A on the Atom.

Release dates are roughly two years apart: the i9-12900E launched on 2022-01-03, and the Atom on 2024-04-07. The i9-12900E has an unlocked multiplier, while the Atom is locked. Launch MSRP is $494 for the i9-12900E and $57 for the Atom. The i9-12900E’s part number is SRL6B; the Atom’s is SRNEM. Neither supports ECC memory, and both are listed as Active in production status.

Where Each One Wins

The Intel Core i9-12900E wins every shared benchmark, making it the clear choice for heavy compute workloads. Its Cinebench R23 multi-core score of 23,529 is nearly 5.3 times the Atom’s 4,435, which positions it for rendering, compilation, and other multi-threaded tasks. The single-core advantage of 430.5% in R23 also makes it superior for everyday responsiveness and lightly threaded applications. With 16 cores and 24 threads, plus 30 MB of L3 cache and dual-channel memory, the i9-12900E is designed for desktop performance where power consumption is not the primary constraint.

The Intel Atom x7405C has no benchmark wins, but its 12 W TDP is its defining characteristic. Where the i9-12900E requires 65 W, the Atom draws a fraction of that, making it suitable for mobile or embedded scenarios where thermal and power budgets are tight. Its single-channel memory and Gen 3 PCIe lanes are modest, but they align with low-power system designs. The Atom’s PassMark scores, such as 14,669 in integer math and 4,004 in data encryption, show it can handle basic processing tasks, but the lack of integrated graphics means a discrete solution is required for display output. The i9-12900E is the performance leader; the Atom x7405C is the efficiency-focused alternative, albeit with a 6-0 loss in direct competition.