AMD EPYC 7351 vs Intel Core i9-11900KB Comparison

The AMD EPYC 7351 and Intel Core i9-11900KB occupy opposite ends of the computing spectrum, yet benchmark results show a remarkably consistent performance relationship. The EPYC 7351 wins all six head-to-head Cinebench comparisons, but the margins are uniformly narrow at 2.2%. Despite having twice the cores and four times the memory bandwidth, the server-focused AMD part only edges out the mobile Intel chip by a small margin in every test. This creates a unique dynamic: the EPYC 7351 is technically the faster processor, but the i9-11900KB achieves near-parity with a fraction of the power envelope.

Where Each One Wins

The AMD EPYC 7351 wins every benchmark category, but the context matters more than the raw score. In multi-core workloads, the EPYC 7351 leverages its 16 cores and 32 threads to post a Cinebench R23 multi-core score of 19742, compared to 19316 for the Intel. That is a 2.2% advantage, which is surprisingly small given the 8-core difference. The EPYC 7351 also leads in single-core tests, scoring 2787 in Cinebench R23 single-core versus 2727 for the Intel, again a 2.2% margin. This suggests the Intel chip's higher 5.30 GHz boost clock compensates significantly for its lower core count.

The Intel Core i9-11900KB wins in efficiency, though no power benchmark is provided. Its 65 W TDP versus the EPYC 7351's 170 W TDP indicates the Intel part delivers over 90% of the multi-core performance at roughly 38% of the thermal design power. The Intel chip also wins on portability and integration, featuring UHD Graphics 750 while the AMD part has no integrated graphics. For users needing a compact BGA 1787 solution, the i9-11900KB is the clear choice, whereas the EPYC 7351's Socket SP3 targets rack-mounted servers.

Architecture Differences

The architectural gap is substantial. The EPYC 7351 uses AMD's Zen architecture on a 14 nm process from GlobalFoundries, while the i9-11900KB uses Intel's Tiger Lake architecture on a 10 nm process. The EPYC 7351 is codenamed Naples and belongs to the EPYC 7001 series, designed for server and workstation workloads. The Intel chip is part of the Core 11th Gen series, codenamed Tiger Lake-H, targeting mobile applications. The production status also differs: the EPYC 7351 is listed as Active, while the i9-11900KB is End-of-life.

Core configurations diverge sharply. The EPYC 7351 packs 16 cores and 32 threads, while the i9-11900KB offers 8 cores and 16 threads. Cache hierarchies are equally distinct: the AMD part provides 96 KB L1 per core, 512 KB L2 per core, and a massive 64 MB shared L3 cache. The Intel chip counters with 80 KB L1 per core, 1.25 MB L2 per core, and 24 MB shared L3. The EPYC 7351's larger L3 cache is typical of server processors designed for data-heavy workloads, while the Intel chip's larger per-core L2 cache (1.25 MB versus 512 KB) suggests an optimization for lower-latency access.

Memory architecture could not differ more. The EPYC 7351 supports DDR4 over an eight-channel memory bus, delivering 170.6 GB/s bandwidth, and includes ECC memory support. The i9-11900KB uses dual-channel DDR4 with 51.2 GB/s bandwidth and lacks ECC support. The EPYC 7351 also supports PCIe Gen 3, while the Intel chip features PCIe Gen 4 with 20 lanes (CPU only). The Intel part includes integrated UHD Graphics 750, a feature absent from the AMD server chip.

Head-to-Head Benchmarks

The Cinebench results show a consistent 2.2% advantage for the EPYC 7351 across all six tests. In Cinebench R15 multi-core, the AMD scores 1989 against 1946 for Intel. Single-core R15 shows 280 versus 274. Moving to Cinebench R20, the EPYC 7351 posts 8291 multi-core and 1170 single-core, while the i9-11900KB manages 8112 and 1145 respectively. The most demanding test, Cinebench R23, shows the AMD leading with 19742 multi-core and 2787 single-core, versus 19316 and 2727 for Intel.

The equal 2.2% delta across every test is striking. This uniformity suggests the performance gap is systematic rather than workload-dependent. The EPYC 7351's advantage stems from its 16-core configuration, but the i9-11900KB's higher clock speeds — 3.30 GHz base and 5.30 GHz boost versus 2.40 GHz base and 2.90 GHz boost — nearly erase the core-count deficit. In single-core tests, the Intel chip's boost clock advantage is expected to dominate, yet the EPYC 7351 still wins by the same 2.2%, indicating the Zen architecture's efficiency at lower clocks is competitive.

Relative to their respective rival pools, the two processors perform differently. The EPYC 7351's average benchmark score is 5710, placing it in the 61st percentile of all CPUs. Its nearest rivals include the AMD EPYC 7F32 (5703, +0.1%), AMD Ryzen Threadripper 2920X (5730, -0.4%), Intel Core i9-7920X (5673, +0.7%), and Intel Xeon W-2175 (5770, -1%). The i9-11900KB averages 5587, also at the 61st percentile, with rivals including Intel Atom x7433RE (5601, -0.2%), Intel Core i7-12700T (5606, -0.3%), AMD Ryzen 7 PRO 3700 (5610, -0.4%), and Intel Celeron G6900 (5561, +0.5%). The Intel chip's average score is 123 points lower than the AMD's, yet both sit at the same percentile.

Specification Differences

The core count is the most obvious differentiator: 16 cores and 32 threads for the EPYC 7351 versus 8 cores and 16 threads for the i9-11900KB. Clock speeds favor Intel significantly, with a 3.30 GHz base and 5.30 GHz boost against 2.40 GHz base and 2.90 GHz boost. Thermal design power favors Intel dramatically: 65 W versus 170 W. The socket types are incompatible: AMD Socket SP3 versus Intel BGA 1787.

Memory bandwidth is a major gap. The EPYC 7351 delivers 170.6 GB/s over eight channels, while the i9-11900KB provides 51.2 GB/s over dual channels. ECC memory is supported only on the AMD part. PCIe generation differs: Gen 3 for AMD, Gen 4 with 20 lanes (CPU only) for Intel. The Intel chip includes UHD Graphics 750, while the AMD has no integrated graphics. Die size is comparable at 213 mm² for AMD and 190 mm² for Intel. The EPYC 7351 uses 14 nm technology from GlobalFoundries, while Intel uses 10 nm from its own foundry. The AMD part has 4,800 million transistors; Intel's transistor count is not listed. The EPYC 7351's launch date is 2017-06-28, while the Intel's release date is not provided.

FAQ

Q: Which processor has more cores?

A: The AMD EPYC 7351 has 16 cores and 32 threads, exactly double the 8 cores and 16 threads of the Intel Core i9-11900KB.

Q: What is the performance difference in Cinebench R23 multi-core?

A: The AMD EPYC 7351 scores 19742 versus 19316 for the Intel Core i9-11900KB, a 2.2% advantage for the AMD part.

Q: Does the Intel Core i9-11900KB have integrated graphics?

A: Yes, it includes UHD Graphics 750. The AMD EPYC 7351 has no integrated graphics.

Q: Which processor supports ECC memory?

A: Only the AMD EPYC 7351 supports ECC memory. The Intel Core i9-11900KB does not.

Q: How do their memory bandwidths compare?

A: The AMD EPYC 7351 offers 170.6 GB/s over eight channels, while the Intel Core i9-11900KB provides 51.2 GB/s over dual channels.

Q: What is the average benchmark score for each processor?

A: The AMD EPYC 7351 averages 5710, and the Intel Core i9-11900KB averages 5587. Both sit at the 61st percentile of all CPUs.

The Verdict

The data points to a clear but nuanced conclusion. For server and workstation workloads where memory bandwidth and ECC support are critical, the AMD EPYC 7351 is the only viable option. Its 170.6 GB/s memory bandwidth, eight-channel bus, and ECC support are non-negotiable features for reliable enterprise computing. The 2.2% performance lead over the Intel chip is a secondary benefit, not the primary reason to choose it.

For mobile or compact computing, the Intel Core i9-11900KB is the better fit. Its 65 W TDP, integrated UHD Graphics 750, and BGA 1787 socket make it suitable for laptops and small form factors. The 5.30 GHz boost clock delivers near-identical single-core performance to the EPYC 7351, trailing by only 2.2%. The Intel chip's end-of-life status is a concern, but its active competitor in the AMD part is a server chip with a 170 W TDP, making it impractical for the Intel's target market.

Users prioritizing raw multi-core performance should choose the EPYC 7351, but they should expect only a marginal gain. The 16-core AMD part beats the 8-core Intel part by just 426 points in Cinebench R23 multi-core. That narrow margin suggests the Intel chip's higher clocks and newer 10 nm process nearly neutralize the AMD's core-count advantage. The EPYC 7351's 61st percentile ranking among all CPUs, matching the i9-11900KB, confirms that these processors are performance equals despite their architectural differences.

The decision ultimately hinges on platform requirements rather than benchmark scores. The EPYC 7351 serves the Socket SP3 server ecosystem with eight-channel memory and ECC. The i9-11900KB serves the mobile BGA 1787 ecosystem with integrated graphics and low power. In a direct performance comparison, the AMD wins all six benchmarks, but the Intel chip's 65 W TDP and 5.30 GHz boost clock make it a compelling alternative for power-constrained applications. The data shows no scenario where the Intel chip outperforms the AMD, but the 2.2% margins are too small to outweigh the substantial platform differences.