Intel Core i5-7600K vs Intel Core i5-8400T Comparison

The Intel Core i5-8400T and the Intel Core i5-7600K are two Coffee Lake- and Kaby Lake-generation desktop processors that land almost side by side in the database rankings, yet they represent opposite design philosophies. The i5-8400T is a 35-watt efficiency part built around six physical cores, while the i5-7600K is a 91-watt performance part with four cores and an unlocked multiplier. Across the eight recorded benchmarks, the i5-8400T wins six and the i5-7600K wins two, but the overall averages sit within a fraction of a percent of each other: 2001 versus 1976. The picture that emerges is one of a low-power hexacore quietly outscoring an older high-clock quad-core in threaded rendering, while the unlocked chip dominates in latency-sensitive and burst-oriented tests.

Head-to-Head Benchmarks

The Cinebench suite tells a strikingly consistent story. In every Cinebench run recorded in the database, the i5-8400T finishes ahead by roughly the same margin. Cinebench R15 multi-core ends at 633 for the 8400T against 583 for the 7600K, an 8.6 percent lead. R20 multi-core repeats the pattern: 2638 against 2432, again 8.5 percent. R23 multi-core lands at 6282 versus 5792, an 8.5 percent gap. These three results are remarkably uniform, which suggests the advantage is structural rather than clock-dependent: the two extra cores of the Coffee Lake part deliver a stable, repeatable throughput edge in sustained rendering workloads regardless of test version.

More surprising is that the i5-8400T also wins every single-core Cinebench test. R15 single-core is 89 against 82, R20 single-core is 372 against 343, and R23 single-core is 886 against 817, margins of 8.5, 8.5, and 8.4 percent respectively. This is counterintuitive given the 7600K's much higher listed clocks, and the recorded data attributes it to the 8400T's newer microarchitecture: Coffee Lake's per-clock gains evidently offset its significantly lower operating frequencies in these tests, at least as measured here.

Geekbench flips the result entirely. In Geekbench single-core the 7600K scores 1522 against the 8400T's 1100, a decisive 27.7 percent advantage. Geekbench multi-core also goes to the 7600K, 4239 versus 4011, a 5.4 percent win despite the 8400T's two extra cores. The database therefore shows a clear split: the 8400T sweeps Cinebench's long-running render tests while the 7600K sweeps Geekbench's shorter, burst-heavy workloads. Aggregate wins stand at six for the 8400T and two for the 7600K.

Architecture Differences

Both chips come from Intel, fabbed on the same 14 nm process node, and both use Intel Socket 1151, which makes them mechanically compatible with the same board family. The architectural gap is generational: the i5-8400T is Coffee Lake, released in April 2018, while the i5-7600K is Kaby Lake, released in January 2017.

The core configuration is the headline difference. The 8400T carries 6 cores and 6 threads; the 7600K carries 4 cores and 4 threads. Neither supports simultaneous multithreading, so physical core count directly defines thread count. Cache also differs: both share the same per-core allocation of 64 KB L1 and 256 KB L2, but the 8400T provides 9 MB of shared L3 against the 7600K's 6 MB, a 50 percent larger last-level cache that pairs naturally with the larger core count.

Clock behavior is inverted. The 7600K runs a 3.80 GHz base and 4.20 GHz boost, while the 8400T is specified far lower at a 1.70 GHz base and 3.30 GHz boost, reflecting its efficiency-first design. Thermal envelopes diverge even more sharply: 35 watts for the 8400T versus 91 watts for the 7600K. The 8400T's die is recorded at 154 mm²; no die size is recorded for the 7600K.

Other shared traits include DDR4 memory support on a dual-channel bus, no ECC support, and PCIe Gen 3 with 16 CPU lanes on both. Memory bandwidth differs slightly, 42.7 GB/s for the 8400T against 38.4 GB/s for the 7600K. Integrated graphics differ in branding: UHD Graphics 630 on the 8400T versus HD 630 on the 7600K. One more key divergence: the 7600K ships with an unlocked multiplier, the 8400T does not. Production status also splits, with the 8400T marked end-of-life while the 7600K remains active in the database.

Where Each One Wins

The i5-8400T wins wherever sustained multi-core throughput matters. The Cinebench record shows it consistently 8.4 to 8.6 percent ahead in both multi-core and single-core rendering tests across three Cinebench generations, meaning content-creation workloads like rendering, encoding-style sustained loads, and anything that scales across six physical cores favors the 8400T. Its database percentile is 45 against the 7600K's 44, and its average score of 2001 edges out the 7600K's 1976.

The i5-7600K wins on responsiveness and burst. Its 27.7 percent Geekbench single-core lead (1522 versus 1100) is the single largest gap in the entire data set, indicating that short, serial, latency-sensitive tasks such as everyday application launches, snappy single-threaded routines, and bursty desktop work run clearly faster on the 7600K. Its 5.4 percent Geekbench multi-core win (4239 versus 4011) further shows that not all threaded work favors the hexacore: workloads made of short parallel bursts favor the higher-clocked quad. Add the unlocked multiplier, and the 7600K is the pick for users who want tuning headroom and peak single-thread speed. The 8400T, by contrast, is the pick for efficiency-constrained systems where a 35-watt envelope must still deliver six-core rendering performance that beats a 91-watt predecessor.

Context from the database rankings reinforces how close these two are. The 8400T's nearest rivals include the AMD Ryzen 7 2800H (average score 2002, effectively identical), the Intel Core i5-8400H (2003), the Intel Xeon D-1712TR (2004), and the Intel Core i5-8300H (2005), all within a fraction of a percent. The 7600K's rivals are the Intel Core i3-N305 (1979), the Intel Xeon E3-1245 v5 (1973), the Intel Core i7-10810U (1971), and the AMD Ryzen 3 2300X (1968), similarly clustered. Both chips occupy the same mid-tier band of the all-CPU rankings.

Specification Differences

The fields where these two processors differ are:

• Cores and threads: 6/6 on the i5-8400T versus 4/4 on the i5-7600K.
• Base clock: 1.70 GHz versus 3.80 GHz.
• Boost clock: 3.30 GHz versus 4.20 GHz.
• TDP: 35 watts versus 91 watts.
• Architecture: Coffee Lake versus Kaby Lake.
• Release date: April 2018 versus January 2017.
• L3 cache: 9 MB shared versus 6 MB shared.
• Die size: 154 mm² recorded for the 8400T; none recorded for the 7600K.
• Memory bandwidth: 42.7 GB/s versus 38.4 GB/s.
• Integrated graphics: UHD Graphics 630 versus HD 630.
• Multiplier: locked on the 8400T, unlocked on the 7600K.
• Production status: end-of-life for the 8400T, active for the 7600K.
• Launch MSRP: $182 recorded for the i5-8400T; no launch MSRP recorded for the i5-7600K.
• Average benchmark score: 2001 versus 1976, and percentile 45 versus 44.

Everything else is common ground: Intel manufacturer, 14 nm process, Intel foundry, Socket 1151, DDR4 on a dual-channel bus, no ECC, PCIe Gen 3 with 16 CPU lanes, and identical per-core L1 and L2 cache sizes.

FAQ

Q: Which processor is faster overall? A: The averages are nearly tied: 2001 for the i5-8400T versus 1976 for the i5-7600K. The 8400T wins 6 of 8 recorded benchmarks, but the 7600K takes both Geekbench tests, including a 27.7 percent single-core win, so the answer depends on workload type.

Q: How much faster is the i5-8400T in rendering? A: It leads every Cinebench test by a consistent 8.4 to 8.6 percent, for example 6282 versus 5792 in Cinebench R23 multi-core and 886 versus 817 in R23 single-core.

Q: Does the i5-7600K win anything? A: Yes. It wins Geekbench single-core 1522 to 1100 and Geekbench multi-core 4239 to 4011, making it the stronger chip for bursty and single-threaded workloads.

Q: Can both chips use the same motherboard? A: Both use Intel Socket 1151, so they share a socket, though the 8400T is the newer Coffee Lake generation (April 2018) versus the 7600K's Kaby Lake generation (January 2017).

Q: Which chip runs cooler? A: The i5-8400T is specified at 35 watts TDP versus 91 watts for the i5-7600K, a substantial efficiency advantage for the 8400T.

Q: Can either processor be overclocked? A: Only the i5-7600K, which has an unlocked multiplier. The i5-8400T's multiplier is locked.