AMD EPYC 7453 vs AMD Ryzen 9 PRO 7945 Comparison

The AMD EPYC 7453 and AMD Ryzen 9 PRO 7945 are both server/workstation processors from AMD, but they are built for fundamentally different scales of work. The EPYC 7453 is a 28-core Zen 3 behemoth designed for socket SP3 platforms, while the Ryzen 9 PRO 7945 is a 12-core Zen 4 part on the mainstream AM5 socket. Data from the benchmark suite shows that the EPYC wins every single head-to-head test, but the margins are surprisingly narrow given the core count disparity. The following analysis breaks down the exact numbers, architectural differences, and the practical implications for each platform.

Head-to-Head Benchmarks

The data is unambiguous: the EPYC 7453 takes all six Cinebench tests, with the winning margins ranging from 3.7% to 3.9%. In the Cinebench R23 multi-core test, the EPYC scores 41,185 against the Ryzen's 39,653, a 3.9% advantage. The single-core results follow the same pattern, with the EPYC's 5,814 in R23 single-core edging out the Ryzen's 5,598 by the same 3.9% delta. This is a consistent sweep across the entire benchmark suite, but the narrowness of the margins is the real story. The EPYC has 16 more cores and 32 more threads than the Ryzen, yet it only leads by roughly 4% in every test. That indicates the Ryzen 9 PRO 7945's higher clock speeds and newer architecture are doing a tremendous amount of heavy lifting to close the gap.

The multi-core results in Cinebench R20 show the EPYC at 17,297 versus the Ryzen's 16,654, a 3.9% lead. In R15 multi-core, the EPYC's 4,151 beats 3,996, also by 3.9%. The single-core tests are nearly identical in proportional terms: R20 single-core is 2,441 vs 2,351 (3.8% lead for EPYC), and R15 single-core is 585 vs 564 (3.7% lead). The fact that the EPYC wins the single-core tests at all is noteworthy, given the Ryzen's 5.40 GHz boost clock versus the EPYC's 3.45 GHz. The benchmark results indicate that the EPYC's Zen 3 architecture, despite being a generation older, delivers superior single-threaded performance per clock in these specific workloads. The Ryzen's average benchmark score is 11,469, which places it near the AMD EPYC 73F3 (11,334, a 1.2% delta) and the AMD EPYC 7402 (11,312, a 1.4% delta). The EPYC 7453's average of 11,912 puts it right alongside the Intel Core i7-7700 (11,914, 0% delta). Both processors sit at the 67th percentile among all CPUs, indicating they are in the same performance tier despite their vastly different configurations.

Architecture Differences

The core architectural split comes down to node, generation, and platform. The EPYC 7453 is built on TSMC's 7 nm process and uses the Zen 3 architecture under the "Milan" codename, part of the EPYC 7003 series. It packs 28 cores and 56 threads with a base clock of 2.75 GHz and a boost clock of 3.45 GHz. The Ryzen 9 PRO 7945 is on the newer 5 nm node with Zen 4 architecture under the "Raphael" codename, belonging to the 7000 series. It has 12 cores and 24 threads, but runs at a much higher 3.70 GHz base and 5.40 GHz boost. The transistor counts differ, with the EPYC using 16,600 million transistors spread across 4x 81 mm² dies, while the Ryzen uses 13,140 million transistors on 2x 71 mm² dies.

Cache configurations are a key differentiator. Both share the same 64 KB L1 cache per core and a 64 MB shared L3 cache, but the L2 cache differs: the EPYC has 512 KB per core, while the Ryzen has 1 MB per core. This doubling of L2 cache per core on the Ryzen helps explain its ability to keep pace in multi-threaded tests despite having fewer cores. Memory support diverges sharply: the EPYC uses DDR4 with an eight-channel memory bus and a massive 204.8 GB/s bandwidth, while the Ryzen uses DDR5 with a dual-channel bus and 83.2 GB/s bandwidth. Both support ECC memory, a critical feature for workstation reliability. The PCIe capabilities also differ dramatically: the EPYC offers Gen 4 with 128 lanes (CPU only), while the Ryzen provides Gen 5 with 24 lanes (CPU only). The Ryzen includes integrated Radeon Graphics, whereas the EPYC has no integrated GPU. The EPYC's 225 W TDP is a stark contrast to the Ryzen's 65 W TDP, a difference that will matter significantly in system design and cooling requirements.

FAQ

Q: Which processor wins in multi-core performance?

A: The AMD EPYC 7453 wins every multi-core test. In Cinebench R23 multi-core, it scores 41,185 versus the Ryzen 9 PRO 7945's 39,653, a 3.9% lead. The margins are consistent across R15 and R20 multi-core tests, all showing a 3.9% advantage for the EPYC.

Q: Is the Ryzen 9 PRO 7945 competitive in single-core workloads?

A: The data shows the EPYC 7453 also wins all single-core tests. In Cinebench R23 single-core, the EPYC scores 5,814 against the Ryzen's 5,598, a 3.9% lead. The Ryzen's higher boost clock of 5.40 GHz is not enough to overcome the EPYC's score in these benchmarks.

Q: What is the TDP difference between the two?

A: The EPYC 7453 has a TDP of 225 W, while the Ryzen 9 PRO 7945 has a TDP of 65 W. This is a substantial difference that affects cooling requirements and system power budgets.

Q: Do both processors support ECC memory?

A: Yes, both the EPYC 7453 and the Ryzen 9 PRO 7945 support ECC memory, making both suitable for error-sensitive workstation and server workloads.

Q: What memory types do they support?

A: The EPYC 7453 supports DDR4 memory with an eight-channel bus and 204.8 GB/s bandwidth. The Ryzen 9 PRO 7945 supports DDR5 memory with a dual-channel bus and 83.2 GB/s bandwidth.

Q: Which processor has more PCIe lanes?

A: The EPYC 7453 offers 128 PCIe Gen 4 lanes (CPU only), while the Ryzen 9 PRO 7945 offers 24 PCIe Gen 5 lanes (CPU only). The EPYC's lane count is far higher, supporting more expansion devices.

Specification Differences

The two processors differ across nearly every major specification field. The EPYC 7453 has 28 cores and 56 threads, while the Ryzen 9 PRO 7945 has 12 cores and 24 threads. The EPYC's base clock is 2.75 GHz and boost is 3.45 GHz, versus the Ryzen's 3.70 GHz base and 5.40 GHz boost. TDP is 225 W for the EPYC and 65 W for the Ryzen. The socket is AMD Socket SP3 for the EPYC and AMD Socket AM5 for the Ryzen. Architecture is Zen 3 (Milan) for the EPYC and Zen 4 (Raphael) for the Ryzen. The process node is 7 nm for the EPYC and 5 nm for the Ryzen. Transistor count is 16,600 million for the EPYC and 13,140 million for the Ryzen. Die size is 4x 81 mm² for the EPYC and 2x 71 mm² for the Ryzen. L2 cache is 512 KB per core for the EPYC and 1 MB per core for the Ryzen. Memory support is DDR4 for the EPYC and DDR5 for the Ryzen. Memory bus is eight-channel for the EPYC and dual-channel for the Ryzen. Memory bandwidth is 204.8 GB/s for the EPYC and 83.2 GB/s for the Ryzen. PCIe is Gen 4 with 128 lanes for the EPYC and Gen 5 with 24 lanes for the Ryzen. The Ryzen includes integrated Radeon Graphics, while the EPYC does not. The release dates are March 14, 2021 for the EPYC and June 12, 2023 for the Ryzen. The EPYC has a launch MSRP of $1570, while the Ryzen has no listed launch MSRP.

The Verdict

The benchmark data points to a clear, if narrow, victory for the EPYC 7453 in all measured Cinebench workloads. With 6 wins and 0 losses in the head-to-head tests, the EPYC is the stronger processor in raw compute performance. The 3.9% lead in every test is consistent and indicates a fundamental performance advantage that scales across both single-core and multi-core workloads. However, the Ryzen 9 PRO 7945 achieves this near-parity with only 12 cores against 28, which is a remarkable efficiency result. The Ryzen's 65 W TDP versus the EPYC's 225 W TDP makes it far more power-efficient per unit of performance. For a server or workstation that needs maximum throughput in threaded applications and has the cooling and power budget to support a 225 W processor, the EPYC 7453 is the right choice based on the data. For systems where power consumption, heat, and platform cost are primary constraints, the Ryzen 9 PRO 7945 offers surprising competitiveness, trailing by only 3.9% at worst while using a fraction of the power. The EPYC's 128 PCIe Gen 4 lanes and eight-channel DDR4 memory with 204.8 GB/s bandwidth make it the superior platform for heavy I/O and memory-bandwidth-bound tasks, while the Ryzen's 24 PCIe Gen 5 lanes and dual-channel DDR5 are more limited. The Ryzen's integrated Radeon Graphics also eliminates the need for a discrete GPU in basic display scenarios.

Where Each One Wins

The EPYC 7453 wins in every benchmark included in the data, so its advantages are clear in raw compute. It also wins in memory bandwidth, with 204.8 GB/s versus 83.2 GB/s, and in PCIe lane count, with 128 Gen 4 lanes versus 24 Gen 5 lanes. This makes it the preferred choice for workloads that scale with core count, such as large-scale virtualization, database serving, and multi-threaded rendering. The eight-channel memory bus provides a substantial bandwidth advantage that benefits memory-intensive applications like scientific computing and in-memory analytics. The 28 cores provide more parallel execution capacity, which the benchmark scores confirm with a 3.9% lead in multi-core tests.

The Ryzen 9 PRO 7945 wins in efficiency and platform flexibility. Its 65 W TDP is dramatically lower than the EPYC's 225 W, making it suitable for compact workstations and environments with strict power budgets. The higher base and boost clocks (3.70 GHz and 5.40 GHz) do not translate to benchmark wins in Cinebench, but they do indicate potential advantages in lightly-threaded workloads that are not represented in this data. The Ryzen's 1 MB L2 cache per core is double the EPYC's 512 KB per core, which can benefit certain cache-sensitive workloads. Its integrated Radeon Graphics provides a display output without a discrete GPU. The newer DDR5 memory support and Gen 5 PCIe offer future-proofing for peripherals that can utilize the increased bandwidth, even though the total bandwidth is lower than the EPYC's older DDR4 eight-channel setup. The Ryzen's release in June 2023 makes it a more recent design, and its position near other EPYC processors in the average benchmark score (11,469 versus 11,334 for EPYC 73F3) shows it is a capable performer in its own right.