CPU Comparison

The Intel Celeron G6900T and Intel Core i5-6400 occupy the same 35th percentile of all CPUs, yet their benchmark profiles could hardly be more different. The i5-6400 dominates the multi-threaded and most single-threaded Cinebench workloads, while the G6900T scores a decisive victory in Geekbench single-core. This head-to-head pits a modern 2-core Alder Lake part against a legacy 4-core Skylake design, with the data revealing a clear split between legacy multi-core grunt and newer single-thread efficiency.

Head-to-Head Benchmarks

The Intel Core i5-6400 wins six of the seven head-to-head comparisons, and its multi-core margins are remarkably consistent. In Cinebench R15 multicore, the i5-6400 scores 364 against the G6900T’s 314, a delta of -13.7% from the Celeron’s perspective. That exact pattern repeats in Cinebench R20 multicore (1517 vs 1309, -13.7%) and Cinebench R23 multicore (3614 vs 3117, -13.8%). The consistency across three generations of the Cinebench suite suggests a stable performance gap driven by the i5-6400’s two additional physical cores, rather than any workload-specific quirk.

The i5-6400 also wins the single-core Cinebench tests, though by a slightly narrower margin. In Cinebench R20 single-core, it scores 214 against 184 for the G6900T, a -14% delta. In Cinebench R23 single-core, the gap is -13.7% (510 vs 440). These are more surprising results, as the G6900T is a newer Alder Lake part with a 10 nm process node, yet the older Skylake chip’s higher boost clock of 3.30 GHz versus the Celeron’s fixed 2.80 GHz appears to outweigh any architectural advantage. The Celeron G6900T has no boost clock at all, which proves decisive in these latency-sensitive, bursty single-thread workloads.

The one bright spot for the Celeron G6900T is Geekbench single-core, where it wins decisively with a score of 1422 against the i5-6400’s 1048. That is a 35.7% advantage for the G6900T, the largest margin in either direction across the entire head-to-head set. This is a striking reversal: in Geekbench’s single-threaded test, the Alder Lake architecture’s newer core design and higher per-core IPC deliver a massive win, even without a boost clock. In Geekbench multicore, however, the i5-6400 reclaims the lead with 3134 versus 2460, a -21.5% delta for the Celeron. That 21.5% gap is the widest multi-core margin in the comparison, reflecting the i5-6400’s 4-core/4-thread configuration against the Celeron’s 2-core/2-thread setup.

Where Each One Wins

The Intel Core i5-6400 is the clear choice for any workload that scales with cores or benefits from sustained multi-threaded throughput. It wins all three Cinebench multicore tests with deltas around -13.7% to -13.8%, and it also takes Geekbench multicore with a -21.5% margin. The i5-6400’s 4 cores and 4 threads, combined with a 6 MB shared L3 cache, give it a structural advantage in rendering, compilation, and other parallel workloads. Additionally, its single-core Cinebench wins (R20 and R23) show that the i5-6400 is not merely a multi-core brute; it can also hold its own in lightly threaded tasks that depend on sustained clock speed, thanks to its 3.30 GHz boost capability.

The Intel Celeron G6900T’s sole victory is in Geekbench single-core, where the 35.7% margin is commanding. This test appears to favor the Alder Lake architecture’s modern core design, which delivers higher instructions-per-clock despite a lower base clock of 2.80 GHz. For users running applications that are heavily dependent on a single thread and that respond well to Geekbench-style integer and floating-point operations, the G6900T offers a distinct advantage. However, the Celeron’s win is isolated; it loses every other benchmark, including both single-core Cinebench tests, which suggests that its architectural edge is not universally applicable across all single-threaded workloads. The practical implication is that the G6900T is better suited to bursty, short-duration single-thread tasks, while the i5-6400 excels in sustained workloads whether single- or multi-threaded.

Architecture Differences

The two processors come from opposite ends of Intel’s design timeline. The G6900T is built on the Alder Lake architecture, specifically the Alder Lake-S codename, using a 10 nm process node from Intel’s own foundry. It is a 2-core, 2-thread part with a base clock of 2.80 GHz and no boost clock. Its cache hierarchy is split differently: 80 KB of L1 per core, 1.25 MB of L2 per core, and 4 MB of shared L3. The G6900T supports both DDR4 and DDR5 memory over a dual-channel bus, and it uses PCIe Gen 5. Its integrated graphics is the UHD Graphics 710, and it is socketed for Intel Socket 1700. The part remains in active production, with a launch MSRP of $42.

The i5-6400, by contrast, is a Skylake-generation part released in mid-2015. It uses a 14 nm process node and a 177 mm² die size. It has 4 cores and 4 threads, with a base clock of 2.70 GHz and a boost clock of 3.30 GHz. Its cache is smaller per core: 64 KB L1, 256 KB L2, but a larger 6 MB shared L3. The i5-6400 only supports DDR4 memory, with a quoted memory bandwidth of 34.1 GB/s, and it uses PCIe Gen 3 with 16 lanes (CPU only). Its integrated graphics is the HD Graphics 530, and it fits Intel Socket 1151. The i5-6400 is marked as end-of-life, and its launch MSRP was $182.

The most significant architectural differences are the process node (10 nm vs 14 nm), core count (2 vs 4), and memory support (DDR4/DDR5 vs DDR4 only). The G6900T’s newer 10 nm node and Alder Lake core design explain its Geekbench single-core dominance, while the i5-6400’s extra cores and larger L3 cache explain its multi-core wins. The i5-6400 also has a boost clock, which the Celeron lacks, and that helps it win the Cinebench single-core tests. The G6900T’s support for PCIe Gen 5 and DDR5 gives it a modern platform advantage, though the i5-6400’s 34.1 GB/s memory bandwidth is a concrete number that the Celeron’s spec sheet does not provide.

FAQ

Q: Which processor has a higher single-core score in Geekbench?

A: The Intel Celeron G6900T wins Geekbench single-core with 1422, which is 35.7% higher than the Intel Core i5-6400’s 1048.

Q: How much faster is the i5-6400 in Cinebench R23 multicore?

A: The i5-6400 scores 3614, versus 3117 for the G6900T, a -13.8% delta from the Celeron’s perspective, meaning the i5-6400 is roughly 14% ahead.

Q: Does the Celeron G6900T support DDR5 memory?

A: Yes, the G6900T supports both DDR4 and DDR5 memory over a dual-channel bus. The i5-6400 only supports DDR4.

Q: What is the core and thread count difference?

A: The G6900T has 2 cores and 2 threads, while the i5-6400 has 4 cores and 4 threads. This explains the i5-6400’s consistent multi-core wins.

Q: Which processor has a boost clock?

A: The i5-6400 has a boost clock of 3.30 GHz, while the G6900T has a base clock of 2.80 GHz and no boost clock. This contributes to the i5-6400’s Cinebench single-core victories.

Q: What is the average benchmark score for each?

A: The G6900T has an average benchmark score of 1321, while the i5-6400 averages 1307. Both sit at the 35th percentile of all CPUs, with the G6900T’s nearest rival being the Celeron G6900E (0% delta) and the i5-6400’s nearest rival being the AMD Opteron 6328 (0.2% delta).

Specification Differences

| Specification | Intel Celeron G6900T | Intel Core i5-6400 |

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

| Cores | 2 | 4 |

| Threads | 2 | 4 |

| Base Clock | 2.80 GHz | 2.70 GHz |

| Boost Clock | None | 3.30 GHz |

| TDP | 35 W | 65 W |

| Socket | Intel Socket 1700 | Intel Socket 1151 |

| Architecture | Alder Lake | Skylake |

| Codename | Alder Lake-S | Skylake |

| Process Node | 10 nm | 14 nm |

| Die Size | Not specified | 177 mm² |

| L1 Cache | 80 KB (per core) | 64 KB (per core) |

| L2 Cache | 1.25 MB (per core) | 256 KB (per core) |

| L3 Cache | 4 MB (shared) | 6 MB (shared) |

| Memory Support | DDR4, DDR5 | DDR4 |

| Memory Bandwidth | Not specified | 34.1 GB/s |

| PCIe | Gen 5 | Gen 3, 16 Lanes (CPU only) |

| Integrated Graphics | UHD Graphics 710 | HD Graphics 530 |

| Production Status | Active | End-of-life |

| Release Date | 2022-01-03 | 2015-07-01 |

| Launch MSRP | $42 | $182 |

| Part Number | SRL68 | SR2L7 |

The specification table reveals a trade-off between modernity and raw resources. The G6900T offers a smaller 35 W TDP, newer PCIe Gen 5, and dual-generation memory support, all on a 10 nm node. The i5-6400 counters with double the cores, a boost clock, a larger 6 MB L3 cache, and a specified memory bandwidth of 34.1 GB/s, at the cost of a 65 W TDP and an older 14 nm process. Neither chip has an unlocked multiplier, and neither supports ECC memory. The i5-6400’s die size of 177 mm² is listed, while the G6900T’s is not provided. These differences map directly onto the benchmark results: the i5-6400’s core count and boost clock drive its Cinebench and Geekbench multicore wins, while the G6900T’s newer core design and process node power its Geekbench single-core victory.