Intel Core i5-8400H vs Intel Core i5-8400T Comparison

The Intel Core i5-8400H and Intel Core i5-8400T are two end-of-life Coffee Lake parts that, despite sharing a family name, target very different physical envelopes—one is a 45 W mobile chip on BGA 1440, the other a 35 W desktop chip on Socket 1151. Both sit at the 45th percentile of all CPUs in the database and post nearly identical average benchmark scores (2003 vs. 2001), yet the head-to-head data reveals a fascinating split: the 8400H wins seven of eight benchmark comparisons, while the 8400T claims a single decisive victory in Geekbench multicore. The story is not about overall speed—it is about how threaded workloads scale differently across these two very different core configurations.

Head-to-Head Benchmarks

The most striking result in the entire comparison is the Geekbench single-core test, where the 8400H leads by 16.5%. The 8400H scores 1281 against the 8400T’s 1100, a gap that far exceeds any other delta in the suite. This is the clearest evidence of the 8400H’s higher boost clock (4.10 GHz vs. 3.30 GHz) translating directly into single-threaded performance. In every Cinebench iteration—R15, R20, and R23—the 8400H wins by a narrow but consistent margin: 1.7% in R15 multicore (644 vs. 633), 1.1% in R15 singlecore (90 vs. 89), 1.7% in R20 multicore (2684 vs. 2638), 1.6% in R20 singlecore (378 vs. 372), and 1.8% in both R23 multicore (6392 vs. 6282) and R23 singlecore (902 vs. 886). These deltas are small, but they are uniform across every Cinebench test, suggesting a consistent per-core advantage for the 8400H rather than a workload-specific quirk.

The outlier is Geekbench multicore, where the 8400T reverses the trend with a score of 4011 versus 3656, an 8.9% margin. This is a significant swing, and it is the only benchmark where the 8400T’s two extra physical cores (6 vs. 4) overcome the 8400H’s higher clock speeds. Notably, the 8400H has 8 threads to the 8400T’s 6, yet the 8400T still wins—which suggests that Geekbench’s multicore test scales more with raw core count than with simultaneous multithreading. The 8400T’s advantage is not reflected in Cinebench, where the 8400H’s hyper-threading appears to compensate for its fewer cores. This divergence between benchmark suites is the central investigative question: why does one test favor the lower-clocked, higher-core-count chip so decisively while the other suite barely notices the difference?

FAQ

Q: Which CPU has the higher single-core performance?

A: The 8400H, by a wide margin. It scores 1281 in Geekbench singlecore versus 1100 for the 8400T (16.5% higher), and it also leads in Cinebench R15, R20, and R23 singlecore tests by margins between 1.1% and 1.8%.

Q: Does the 8400T ever outperform the 8400H?

A: Yes, in exactly one benchmark: Geekbench multicore. The 8400T scores 4011 against the 8400H’s 3656, an 8.9% advantage. It loses all three Cinebench multicore tests, however, with deltas of 1.7% to 1.8% in favor of the 8400H.

Q: How do their average benchmark scores compare?

A: The 8400H averages 2003 across all benchmarks, while the 8400T averages 2001—a difference of roughly 0.1%. Both CPUs are listed as nearest rivals to each other, with the 8400H showing a deltaPct of 0.1% over the 8400T, and the 8400T showing -0.1% relative to the 8400H.

Q: What is the core and thread configuration for each?

A: The 8400H has 4 cores and 8 threads, while the 8400T has 6 cores and 6 threads. This means the 8400H relies on hyper-threading to reach 8 threads, whereas the 8400T has more physical cores but no hyper-threading.

Q: Which chip has the larger L3 cache?

A: The 8400H has 12 MB of shared L3 cache, while the 8400T has 9 MB. Both use 64 KB of L1 and 256 KB of L2 per core.

Q: Are these CPUs from the same architecture generation?

A: Yes, both are Coffee Lake on a 14 nm process from Intel. The 8400H’s codename is Coffee Lake-H, while the 8400T is simply Coffee Lake. Both were released on the same date and are marked end-of-life.

Where Each One Wins

The 8400H is the clear winner for single-threaded and lightly threaded workloads. Its Geekbench singlecore score of 1281 is 16.5% above the 8400T, and it maintains a lead in every Cinebench singlecore test. This makes it the better choice for applications that rely on high clock speeds per core—think legacy software, certain game engines that favor a few fast cores, or any task that cannot fully utilize more than four threads. The data also shows the 8400H winning all three Cinebench multicore tests, meaning it is not a slouch in multithreaded rendering either; its 8 threads and higher boost clock (4.10 GHz) appear to be a winning combination in that specific benchmark suite.

The 8400T’s sole victory is Geekbench multicore, where its 6 physical cores produce a 4011 score versus 3656. This suggests that in workloads specifically tuned to scale with physical core count rather than thread count—or where Geekbench’s particular scheduling and memory access patterns favor more cores—the 8400T has a real edge. The 8400T also offers a dual-channel memory bus with 42.7 GB/s bandwidth, whereas the 8400H’s memory bus is not specified in the data; that could contribute to its multicore advantage in memory-sensitive tests. For users running heavily parallel, core-count-hungry applications that resemble Geekbench’s multicore workload, the 8400T is the more capable part.

Specification Differences

The two CPUs differ in almost every physical and electrical specification. The 8400H has a 2.50 GHz base clock and 4.10 GHz boost clock, while the 8400T has a 1700.00 MHz base clock (the unusual decimal suggests a data entry quirk, but the figure is as provided) and a 3.30 GHz boost clock. The 8400H is rated at 45 W TDP, the 8400T at 35 W. The 8400H uses Intel BGA 1440 socket, while the 8400T uses Intel Socket 1151. The 8400H has a die size of 126 mm², while the 8400T is larger at 154 mm². The 8400T is explicitly listed with dual-channel memory support and 42.7 GB/s bandwidth, while the 8400H lists only DDR4 memory support with no bus or bandwidth details. The 8400T lists PCIe as Gen 3 with 16 lanes (CPU only), while the 8400H has no PCIe information. The 8400H’s integrated graphics are listed as UHD 630, while the 8400T’s are UHD Graphics 630—a naming difference that may be cosmetic. The 8400T has a launch MSRP of $182; the 8400H has no launch MSRP data.

Architecture Differences

Both are Coffee Lake on Intel’s 14 nm process, but they diverge in core configuration and cache layout. The 8400H uses 4 cores with 8 threads (hyper-threading enabled), while the 8400T uses 6 cores with 6 threads (no hyper-threading). The 8400H has 12 MB of shared L3 cache, while the 8400T has 9 MB. Both share the same per-core L1 (64 KB) and L2 (256 KB) sizes. The 8400H’s codename is Coffee Lake-H, indicating a mobile-optimized variant, while the 8400T is plain Coffee Lake for desktop. The 8400H’s smaller die size (126 mm² vs. 154 mm²) is consistent with its fewer cores and mobile packaging. Neither chip supports ECC memory, and neither has an unlocked multiplier. Both are end-of-life and were released on the same date in April 2018. The 8400H belongs to the Core i5 (Coffee Lake-H) generation, while the 8400T belongs to the Core i5 (Coffee Lake) generation.

The Verdict

From the data, the 8400H is the superior all-around performer for most workloads. It wins 7 of 8 head-to-head benchmarks, including every Cinebench test and Geekbench singlecore. Its 16.5% single-core lead is decisive, and its consistency across the Cinebench suite—where it wins multicore by 1.7% to 1.8% despite having fewer physical cores—shows that its hyper-threading and higher clock speeds are effective in rendering workloads. Anyone prioritizing per-core speed, gaming, or Cinebench-style rendering should choose the 8400H.

The 8400T is the pick only for a narrow use case: applications that mirror Geekbench’s multicore test, where its 6 physical cores yield an 8.9% advantage over the 8400H. Its lower TDP (35 W vs. 45 W) and desktop socket may also matter for system builders who prefer a standard Socket 1151 platform, and it is the only one of the two with a stated launch MSRP ($182). But for users who do not have a specific need for that Geekbench multicore pattern, the 8400H’s near-total dominance in the benchmark data makes it the more versatile choice. The average scores (2003 vs. 2001) are nearly identical, but the distribution of wins is lopsided: the 8400H wins everywhere except one test, and that one loss is the only reason this is not a clean sweep.