CPU Comparison
Intel Core i3-10105F
Core i5-8400
PERFORMANCE BENCHMARKS
Analysis: Intel Core i3-10105F vs Intel Core i5-8400
The Intel Core i5-8400 and Intel Core i3-10105F present a classic generational clash, where the older six-core part leverages its physical core count, while the newer four-core part counters with higher clocks and Hyper-Threading. Benchmark results show the i5-8400 wins the majority of tests, taking 12 of 19 head-to-head comparisons, but the i3-10105F is far from obsolete, securing 7 wins that highlight its strengths in specific workloads. The data indicates a split decision: the i5-8400 is the superior all-rounder for multithreaded and floating-point tasks, while the i3-10105F excels in integer-heavy and single-threaded scenarios.
Head-to-Head Benchmarks
The i5-8400 establishes its dominance in rendering and general multithreaded workloads. In Cinebench R23 multi-core, it scores 7847 against the i3-10105F’s 7537, a 4.1% lead. This pattern repeats across Cinebench R15 (790 vs 759) and R20 (3295 vs 3165), with the same 4.1% delta. The i5-8400’s advantage extends to Geekbench multi-core, where it posts 5088 versus 4920, a 3.4% margin, and PassMark multi-thread, where it wins 9225 to 8930 (3.3%).
The most dramatic disparity appears in PassMark extended instructions, where the i5-8400 scores 11543 against the i3-10105F’s 8753, a commanding 31.9% advantage. A similar chasm opens in floating-point math, with the i5-8400 at 22006 versus 18166, a 21.1% lead. The i5-8400 also wins PassMark physics by 11.2% (635 vs 571) and finds prime numbers 48% faster (37 vs 25), showcasing its superiority in complex mathematical operations.
The i3-10105F, however, strikes back decisively in single-threaded and integer-focused tests. Its Geekbench single-core score of 1470 beats the i5-8400’s 1353 by 8%. PassMark single-thread confirms this, with the i3-10105F scoring 2647 versus 2371, a 10.4% advantage. In PassMark integer math, the i3-10105F posts 28921 against 25573, winning by 11.6%. Data compression and encryption also favor the i3-10105F, with narrow wins of 0.5% (130647 vs 129951) and 7.3% (3045 vs 2824) respectively. Random string sorting goes to the i3-10105F by 2.8% (16414 vs 15952).
Where Each One Wins
The i5-8400 is the clear winner for multithreaded productivity and compute-heavy tasks. Its six physical cores provide a robust foundation for Cinebench rendering, where it wins every multi-core variant by 4.1%. The 31.9% lead in extended instructions and 21.1% lead in floating-point math indicate strong performance for scientific computing, video encoding, and simulations that rely on AVX or similar instruction sets. The 48% advantage in prime-number finding further cements its role for integer-heavy algorithmic workloads.
The i3-10105F claims the single-threaded crown, winning Geekbench single-core by 8% and PassMark single-thread by 10.4%. This translates to superior responsiveness in lightly threaded applications like legacy games, office suites, and basic web browsing. Its 11.6% win in integer math makes it better suited for database operations, compression tools, and encryption tasks, evidenced by its wins in data compression (0.5%) and data encryption (7.3%). The i3-10105F also takes random string sorting, indicating strength in sorting algorithms and text processing.
Architecture Differences
The i5-8400 is built on the Coffee Lake architecture using a 14 nm process, while the i3-10105F uses Comet Lake-R, also on 14 nm. Both share the same foundry (Intel) and dual-channel DDR4 memory support with 42.7 GB/s bandwidth. The i5-8400 uses Intel Socket 1151, whereas the i3-10105F requires Intel Socket 1200, making them incompatible across motherboards.
Core configurations diverge significantly. The i5-8400 has 6 cores and 6 threads, lacking Hyper-Threading, which explains its consistent 4.1% lead in multithreaded Cinebench tests, the extra physical cores outweigh the i3-10105F’s 4 cores and 8 threads. The i3-10105F compensates with a higher base clock (3.70 GHz vs 2.80 GHz) and boost clock (4.40 GHz vs 4.00 GHz), driving its single-threaded wins.
Cache allocations differ: the i5-8400 has 9 MB of shared L3 cache, while the i3-10105F has only 6 MB. Both have the same per-core L1 (64 KB) and L2 (256 KB) cache sizes. The integrated graphics also diverge, the i5-8400 includes UHD Graphics 630, while the i3-10105F has no integrated graphics, requiring a discrete GPU for display output. Both CPUs are unlocked-free (multiplier locked) and support PCIe Gen 3 with 16 lanes (CPU only).
Specification Differences
The core and thread count is the primary differentiator: the i5-8400 has 6 cores and 6 threads, versus the i3-10105F’s 4 cores and 8 threads. Clock speeds favor the i3-10105F, with a base clock of 3.70 GHz compared to 2.80 GHz, and a boost clock of 4.40 GHz versus 4.00 GHz. The L3 cache is larger on the i5-8400 at 9 MB shared, while the i3-10105F has 6 MB shared.
The socket changes from Intel Socket 1151 (i5-8400) to Intel Socket 1200 (i3-10105F). The i5-8400 has integrated graphics (UHD Graphics 630), whereas the i3-10105F has none. Release dates differ: the i5-8400 launched on 2017-10-04, while the i3-10105F launched on 2021-03-15. The i5-8400 is end-of-life with part number SLAPL, while the i3-10105F remains active with part number SRH8V. The die size is listed only for the i5-8400 at 154 mm²; the i3-10105F’s die size is unavailable.
FAQ
Q: Which CPU has more cores?
A: The Intel Core i5-8400 has 6 cores and 6 threads, while the Intel Core i3-10105F has 4 cores and 8 threads.
Q: Does the i3-10105F beat the i5-8400 in any multithreaded benchmark?
A: No. The i5-8400 wins all multithreaded tests, including Cinebench R20 multicore (3295 vs 3165, 4.1% lead) and PassMark multithread (9225 vs 8930, 3.3% lead).
Q: Why does the i3-10105F win single-threaded tests despite having fewer cores?
A: The i3-10105F has a higher boost clock of 4.40 GHz versus 4.00 GHz, and a higher base clock of 3.70 GHz versus 2.80 GHz, which drives its 10.4% win in PassMark single-thread and 8% win in Geekbench single-core.
Q: Do both CPUs support the same memory bandwidth?
A: Yes, both support dual-channel DDR4 memory with a bandwidth of 42.7 GB/s.
Q: Are these CPUs socket-compatible with each other?
A: No. The i5-8400 uses Intel Socket 1151, while the i3-10105F uses Intel Socket 1200.
Q: Which CPU has integrated graphics?
A: Only the Intel Core i5-8400 has integrated graphics (UHD Graphics 630); the Intel Core i3-10105F has none.
The Verdict
The data points to the Intel Core i5-8400 as the superior processor for most workloads. It wins 12 of 19 benchmarks, including every Cinebench test (multi and single core), Geekbench multicore, and PassMark multithread. Its 31.9% lead in extended instructions and 21.1% lead in floating-point math make it the choice for compute-heavy applications. The 4.1% Cinebench multi-core advantage across all versions confirms its strength in rendering and video editing.
However, the Intel Core i3-10105F has a clear niche. Its 10.4% single-thread win and 11.6% integer math advantage make it better for everyday desktop tasks, data compression, and encryption. The 7.3% win in data encryption and 8% Geekbench single-core lead suggest snappier performance in lightly threaded software. For users who prioritize single-thread responsiveness and integer workloads, the i3-10105F is the pick. For everyone else, particularly those running multithreaded applications or floating-point-heavy code, the i5-8400 is the verdict from the benchmark results.