Intel Core i5-8400T vs Intel Core i7-7920HQ Comparison

This comparison pits two end-of-life Intel processors with very different design goals against each other. The Intel Core i5-8400T is a 35 W desktop part built for compact, low-power systems, while the Intel Core i7-7920HQ is a 45 W mobile chip designed for high-performance laptops. Despite the i7’s higher tier name and much higher launch MSRP, the benchmark data shows a surprisingly close contest, with the desktop i5 taking the majority of wins.

Where Each One Wins

The Intel Core i5-8400T dominates this matchup on paper, winning 7 out of 8 head-to-head benchmarks. Its victories are consistent across every Cinebench test, covering both R15, R20, and R23 versions, and in both single-core and multi-core workloads. The margin is narrow but real, ranging from 2.1% to 2.3% in those tests. It also edges out the i7 in Geekbench multi-core, though only by 0.3%, which is essentially a tie.

The Intel Core i7-7920HQ’s single win is a significant one in Geekbench single-core, where it beats the i5 by 13.2%. This is the largest performance gap in either direction across all benchmarks. This suggests the i7 has a clear advantage in lightly-threaded, latency-sensitive tasks that rely heavily on raw clock speed rather than core count.

The practical split comes down to workload type. For sustained multi-threaded rendering, video encoding, or any task that scales with core count, the i5-8400T holds the advantage. For snappy single-threaded response in older applications or games that favor high clock speeds, the i7-7920HQ has the edge, despite its lower core count.

Architecture Differences

The two chips come from different Intel generations and are built for different sockets. The i5-8400T uses the Coffee Lake architecture on Intel Socket 1151, while the i7-7920HQ uses Kaby Lake-H on Intel BGA 1440. Both are fabricated on Intel’s 14 nm process, but the die sizes differ notably: the i5 has a 154 mm² die, while the i7 is smaller at 126 mm².

Core and thread counts are where the fundamental design split appears. The i5-8400T offers 6 physical cores with 6 threads, meaning no hyper-threading. The i7-7920HQ has 4 physical cores with 8 threads, relying on hyper-threading to reach its thread count. This is a classic trade-off: more physical cores versus more threads per core.

Cache configurations also differ. The i5-8400T has 9 MB of shared L3 cache, while the i7-7920HQ has 8 MB. Both have identical per-core L1 and L2 caches at 64 KB and 256 KB per core respectively. The i5’s larger total L3 cache is consistent with its higher core count.

Memory support diverges as well. The i5-8400T supports DDR4 memory only, with a rated memory bandwidth of 42.7 GB/s. The i7-7920HQ supports both DDR3 and DDR4, with no memory bandwidth figure listed in the data. Both use dual-channel memory buses.

Integrated graphics differ in branding: the i5 uses UHD Graphics 630, while the i7 uses Intel HD Graphics 630. Both are end-of-life products, but the i5 was released later, in April 2018, versus January 2017 for the i7.

Head-to-Head Benchmarks

The Cinebench results paint a consistent picture. In Cinebench R15 multi-core, the i5-8400T scores 633 against the i7’s 619, a 2.3% win. In single-core R15, the i5 wins again with 89 versus 87, also 2.3%. Moving to R20, the i5 scores 2638 multi-core and 372 single-core, compared to 2583 and 364 for the i7, yielding wins of 2.1% and 2.2% respectively.

Cinebench R23 continues the trend. The i5-8400T posts 6282 multi-core and 886 single-core, while the i7-7920HQ posts 6151 and 868. The i5 wins both by 2.1%. These results are remarkably consistent across all three Cinebench versions, suggesting the i5’s advantage is structural rather than workload-specific.

Geekbench tells a more complex story. In multi-core, the i5-8400T scores 4011 against the i7’s 3999, a minimal 0.3% edge. This is effectively a statistical tie. In single-core, the tables turn dramatically: the i7-7920HQ scores 1267 against the i5’s 1100, a 13.2% victory. This is the single largest delta in the entire comparison.

The data shows the i5-8400T’s 6 physical cores beat the i7’s 4 cores with 8 threads in every multi-threaded test, but by a smaller margin than one might expect. Conversely, the i7’s higher base and boost clocks (3.10 GHz base and 4.10 GHz boost versus 1.70 GHz base and 3.30 GHz boost) give it a clear edge in single-threaded Geekbench performance. The Cinebench single-core tests, however, do not reflect this advantage, which is worth noting.

The Verdict

From the data alone, the Intel Core i5-8400T is the better performer overall. It wins 7 of 8 benchmarks, including all multi-core tests and all Cinebench tests in both single and multi-core modes. Its average benchmark score of 2001 is also slightly higher than the i7’s 1992. The i5 sits at the 45th percentile among all CPUs, versus the i7’s 44th percentile.

The i5-8400T is the pick for anyone building a desktop system where multi-threaded performance matters more than peak single-core speed. Its 35 W TDP makes it suitable for systems where cooling is limited. The i7-7920HQ, on the other hand, is a mobile part with a 45 W TDP, and its 13.2% Geekbench single-core win suggests it may feel snappier in some everyday tasks.

However, the practical difference between these two in most workloads is small. The largest multi-core gap is just 2.3%, and the i7’s single-core win in Geekbench is an outlier relative to its Cinebench single-core losses. For a buyer choosing between a desktop and a laptop platform, the i5-8400T offers more consistent performance at a lower launch MSRP of $182 versus the i7’s $568. But strictly on benchmark scores, the i5 is the winner.

FAQ

Q: Which processor has more cores?

A: The Intel Core i5-8400T has 6 physical cores, while the Intel Core i7-7920HQ has 4 physical cores.

Q: Which processor has higher clock speeds?

A: The Intel Core i7-7920HQ has higher clocks, with a 3.10 GHz base and 4.10 GHz boost, versus the i5-8400T’s 1.70 GHz base and 3.30 GHz boost.

Q: Does the i7-7920HQ beat the i5-8400T in any benchmark?

A: Yes, the i7-7920HQ wins Geekbench single-core with a score of 1267 versus 1100, a 13.2% advantage.

Q: How big is the multi-core performance gap?

A: The i5-8400T leads by 2.3% in Cinebench R15 multi-core (633 vs 619), 2.1% in R20 (2638 vs 2583), and 2.1% in R23 (6282 vs 6151).

Q: Are both processors end-of-life products?

A: Yes, both the Intel Core i5-8400T and Intel Core i7-7920HQ are listed as end-of-life.

Q: Which processor has a smaller die size?

A: The Intel Core i7-7920HQ has a smaller die at 126 mm², compared to the i5-8400T’s 154 mm².

Specification Differences

| Specification | Intel Core i5-8400T | Intel Core i7-7920HQ |

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

| Cores | 6 | 4 |

| Threads | 6 | 8 |

| Base Clock | 1700.00 MHz | 3100.00 MHz |

| Boost Clock | 3.30 GHz | 4.10 GHz |

| TDP | 35 W | 45 W |

| Socket | Intel Socket 1151 | Intel BGA 1440 |

| Architecture | Coffee Lake | Kaby Lake |

| Codename | Coffee Lake | Kaby Lake-H |

| Die Size | 154 mm² | 126 mm² |

| L3 Cache | 9 MB (shared) | 8 MB (shared) |

| Memory Support | DDR4 | DDR3, DDR4 |

| Memory Bandwidth | 42.7 GB/s | Not listed |

| Integrated Graphics | UHD Graphics 630 | Intel HD Graphics 630 |

| Market Segment | Desktop | Mobile |

| Release Date | 2018-04-01 | 2017-01-02 |

| Launch MSRP | $182 | $568 |

| Part Number | SR3X6 | SR32L |