CPU Comparison

The Intel Core i7-6700 and AMD Ryzen Threadripper 3970X represent two entirely different eras and market positions. The data shows a decisive victory for the Threadripper, which wins all eight head-to-head benchmark comparisons. However, the Core i7-6700 still holds relevance in specific legacy scenarios. The Threadripper 3970X is the clear choice for heavy multi-threaded workloads, while the Core i7-6700 serves as a functional, lower-power option for basic desktop tasks where its 65W TDP and integrated graphics provide an edge in system simplicity.

The Verdict

The benchmark results are unambiguous: the AMD Ryzen Threadripper 3970X is the superior processor in every measured category. It wins 8 out of 8 head-to-head comparisons, with the largest margin being an 87.3% advantage in multi-core Cinebench tests. The Core i7-6700, with its 4 cores and 8 threads, cannot compete with the Threadripper's 32 cores and 64 threads in any workload that scales with core count.

For users whose primary concern is raw compute throughput, the Threadripper 3970X is the only rational choice. Its Cinebench R23 multi-core score of 53630 dwarfs the Core i7-6700's 6828, representing a roughly 7.9x performance advantage. Even in single-core tests, the Threadripper leads by 87.3% in Cinebench R23 single-core (7571 vs 964), which is unexpected given the Core i7-6700's higher boost clock relative to its own core count.

The Core i7-6700 is not without merit, but its role is limited. With a 65W TDP versus 280W, it is far more power-efficient for basic tasks. It also includes integrated graphics (HD Graphics 530), which the Threadripper lacks entirely. For a simple office PC or a legacy system where no discrete GPU is desired, the Core i7-6700 remains functional. However, its percentile rank of 66 places it in the same performance tier as the Threadripper's 66th percentile, which is misleading given the massive absolute score differences.

Where Each One Wins

The Threadripper 3970X wins every benchmark in the head-to-head comparison, but the nature of those wins varies. In multi-core workloads, the advantage is overwhelming. The Cinebench R15, R20, and R23 multi-core tests all show the Threadripper leading by 87.3%. Geekbench multi-core shows a 79.1% advantage (20112 vs 4201). These results reflect the Threadripper's 32-core, 64-thread configuration, which allows it to excel in rendering, video encoding, and scientific computing.

Single-core performance is closer but still favors the Threadripper. The 87.3% single-core delta in Cinebench tests is notable, while Geekbench single-core shows a smaller 23.5% gap (1653 vs 1264). This suggests the Threadripper's higher boost clock of 4.50 GHz provides a meaningful advantage over the Core i7-6700's 4.00 GHz boost, even in lightly-threaded tasks.

The Core i7-6700 has no benchmark wins, but it wins in system-level attributes. Its 65W TDP means it can be cooled by a basic air cooler, while the Threadripper's 280W TDP requires substantial cooling solutions. The Core i7-6700 also supports DDR3 and DDR4 memory, offering flexibility for older systems, whereas the Threadripper is DDR4-only. For users with existing DDR3 memory, the Core i7-6700 avoids the cost of new RAM.

Architecture Differences

The architectural gap between these processors is generational. The Core i7-6700 uses Intel's Skylake architecture on a 14nm process node, fabricated by Intel. It has 4 cores and 8 threads, with a base clock of 3.40 GHz and a boost clock of 4.00 GHz. Its cache hierarchy includes 64 KB of L1 per core, 256 KB of L2 per core, and 8 MB of shared L3 cache. Memory support includes both DDR3 and DDR4, with dual-channel bandwidth of 34.1 GB/s. It uses PCIe Gen 3 with 16 lanes from the CPU and includes integrated HD Graphics 530.

The Threadripper 3970X is built on AMD's Zen 2 architecture, codenamed Castle Peak, using a 7nm process node fabricated by TSMC. This process advantage allows for a much denser chip, with 15,200 million transistors spread across four 74 mm² dies. It has 32 cores and 64 threads, with a base clock of 3.70 GHz and a boost clock of 4.50 GHz. Cache is significantly larger: 64 KB L1 per core, 512 KB L2 per core, and a massive 128 MB of L3 cache. Memory support is DDR4 only, but the quad-channel bus provides 102.4 GB/s of bandwidth, three times the Core i7-6700's dual-channel figure. It uses PCIe Gen 4 and has no integrated graphics.

The Threadripper also has an unlocked multiplier, allowing overclocking, while the Core i7-6700's multiplier is locked. The Threadripper's production status is Active, while the Core i7-6700 is End-of-life. The launch MSRP for the Core i7-6700 was $303, while the Threadripper 3970X launched at $1999.

FAQ

Q: Which processor is faster in multi-core rendering?

A: The Threadripper 3970X is overwhelmingly faster. In Cinebench R23 multi-core, it scores 53630 versus the Core i7-6700's 6828, an 87.3% advantage. The same 87.3% delta applies to Cinebench R15 and R20 multi-core tests.

Q: Does the Core i7-6700 have any advantage over the Threadripper?

A: Yes, in system-level attributes. The Core i7-6700 has a 65W TDP versus 280W, includes integrated HD Graphics 530, and supports both DDR3 and DDR4 memory. The Threadripper has no integrated graphics and is DDR4-only.

Q: How does single-core performance compare?

A: The Threadripper wins all single-core tests. Geekbench single-core shows a 23.5% gap (1653 vs 1264), while Cinebench R23 single-core shows an 87.3% gap (7571 vs 964). The Threadripper's higher 4.50 GHz boost clock contributes to this.

Q: What memory bandwidth do these processors support?

A: The Core i7-6700 supports dual-channel memory with 34.1 GB/s bandwidth. The Threadripper 3970X supports quad-channel memory with 102.4 GB/s bandwidth.

Q: Are these processors still in production?

A: The Core i7-6700 is End-of-life, released on 2015-06-30. The Threadripper 3970X is Active, released on 2019-11-24.

Q: Can the Core i7-6700 be overclocked?

A: No, its multiplier is locked. The Threadripper 3970X has an unlocked multiplier, allowing overclocking.

Head-to-Head Benchmarks

The most striking result is in Cinebench R23 multi-core, where the Threadripper scores 53630 against the Core i7-6700's 6828. This 87.3% delta is the largest of any test. The Threadripper's 32 cores provide a massive parallel throughput advantage, making it ideal for 3D rendering and video encoding. The Core i7-6700's 4 cores are simply outclassed in this scenario.

Geekbench multi-core shows a 79.1% advantage (20112 vs 4201), which is slightly smaller than the Cinebench deltas but still decisive. This test measures a broader range of integer and floating-point workloads, and the Threadripper's 64 threads allow it to handle multiple simultaneous tasks with ease.

Single-core performance is closer in Geekbench, with the Threadripper leading by 23.5% (1653 vs 1264). This is the smallest delta of all head-to-head tests. The Core i7-6700's Skylake architecture was strong for its time, and its 4.00 GHz boost clock helps in lightly-threaded applications. However, the Threadripper's 4.50 GHz boost clock and newer Zen 2 architecture still give it a clear win.

Cinebench R15 and R20 tests show consistent 87.3% deltas in both multi-core and single-core modes. The R15 single-core test (762 vs 96) and R20 single-core test (3179 vs 404) both demonstrate that the Threadripper's architectural improvements extend to single-thread performance as well. The Core i7-6700's scores are not just lower; they are an order of magnitude lower in multi-core tests.

The Threadripper's 3DMark results, while not in the head-to-head table, provide additional context. It scores 16588 in max threads, 10154 in 16 threads, 5263 in 8 threads, 2777 in 4 threads, 1436 in 2 threads, and 724 in single thread. These numbers show that the Threadripper scales well across all thread counts, reinforcing its versatility.

In the benchmark database, the Core i7-6700 has an average benchmark score of 11074, while the Threadripper scores 10841. This is a quirk of the averaging methodology, as the Core i7-6700's nearest rivals include the AMD EPYC 9224 (-0.4%), AMD EPYC 7542 (-0.7%), AMD Ryzen 5 3500U (-0.9%), and Intel Xeon Gold 6336Y (-1%). The Threadripper's nearest rivals include the Intel Core i7-6700 (-2.1%), AMD EPYC 9224 (-2.5%), Intel Core i7-4790 (2.7%), and AMD EPYC 7D12 (2.8%). Both processors share the 66th percentile, indicating similar relative standing in the full CPU database, but the raw scores tell a different story.

The Core i7-6700's PassMark results show its strengths in specific tasks: data compression at 113748, integer math at 25651, and floating-point math at 15840. Its single-thread score of 2277 is respectable for a 2015 processor. However, these figures cannot offset the Threadripper's fundamental advantage in core count and modern architecture. For users building a new system today, the Threadripper 3970X is the only logical choice for demanding workloads, while the Core i7-6700 remains a viable option only for cost-constrained legacy builds where its integrated graphics and low power draw are valued.