AMD Ryzen 9 9950X3D vs Intel Xeon 638 Comparison

The Intel Xeon 638 and AMD Ryzen 9 9950X3D are both 16-core, 32-thread processors, but the data reveals two very distinct performance profiles. The head-to-head benchmark results show a clear split: the Intel part dominates in specific legacy and single-threaded Cinebench tests, while the AMD part is the overwhelming favorite across the Passmark suite. Of the 15 recorded head-to-head comparisons, the AMD Ryzen 9 9950X3D takes 12 wins, leaving the Intel Xeon 638 with only 3.

Head-to-Head Benchmarks

The most significant Intel victories come in the Cinebench R23 single-core test, where the Xeon 638 scores 6663 against AMD's 2259. This is a 195% delta, the largest single gap in the entire comparison. The Xeon also dominates the Cinebench R15 single-core test, scoring 671 versus 350, a 91.7% lead, which highlights a massive advantage in lightly threaded legacy rendering tasks. The Intel chip also wins the Cinebench R23 multi-core test, posting 47202 against AMD's 42018, a 12.3% improvement, which is notable given both parts have identical core and thread counts.

The AMD Ryzen 9 9950X3D, however, is the clear victor almost everywhere else. In Cinebench R15 multi-core, the AMD part scores 6536 versus Intel's 4757, a 27.2% lead. The PassMark suite shows a consistent AMD advantage, starting with integer math, where AMD scores 243209 against Intel's 184884, a 24% delta. The AMD chip is also 37.8% ahead in the find prime numbers test, scoring 613 versus 381. Data compression and encryption workloads favor AMD by 20.1% and 19.1%, respectively, with scores of 908421 versus 725818 and 44536 versus 36030.

In floating-point math, the AMD part holds a 9.4% lead, posting 159724 against 144757. The PassMark multithread score also goes to AMD, with 70255 versus Intel's 55651, a 20.8% delta. The single-threaded PassMark test is also an AMD win at 4737 versus 3670, which represents a 22.5% gap, contradicting the Cinebench single-core results. Physics, extended instructions, and random string sorting all follow the same pattern. AMD wins physics 5670 to 4704, extended instructions 73011 to 56498, and random string sorting 95423 to 74318, with deltas of 17.0%, 22.6%, and 22.1% respectively.

FAQ

Q: Which CPU has the higher clock speed?

A: The AMD Ryzen 9 9950X3D has a base clock of 4.30 GHz and a boost clock of 5.70 GHz. The Intel Xeon 638 has a lower base clock of 3.20 GHz and a boost clock of 4.80 GHz.

Q: How do the two processors compare in cache capacity?

A: The AMD Ryzen 9 9950X3D has 128 MB of L3 cache, whereas the Intel Xeon 638 has 72 MB of shared L3 cache. The Intel part has larger per-core L1 and L2 caches at 112 KB and 2 MB, while AMD has 80 KB and 1 MB per core.

Q: Which processor uses more power?

A: The Intel Xeon 638 has a TDP of 180 watts, while the AMD Ryzen 9 9950X3D is rated at 170 watts.

Q: What are the memory bandwidth capabilities of each?

A: The Intel Xeon 638 has a quad-channel memory bus with a bandwidth of 204.8 GB/s. The AMD Ryzen 9 9950X3D has a dual-channel memory bus and a bandwidth of 89.6 GB/s. Both support DDR5 memory and ECC.

Q: Which CPU has a higher average benchmark score?

A: The Intel Xeon 638 has an average benchmark score of 80723, while the AMD Ryzen 9 9950X3D has an average score of 75779. Both are in the 95th percentile of all CPUs.

Q: Are these processors unlocked for overclocking?

A: Yes, both the Intel Xeon 638 and the AMD Ryzen 9 9950X3D have an unlocked multiplier.

Architecture Differences

The Intel Xeon 638 is built on the Granite Rapids architecture, a 5 nm process from Intel, and uses a large die size of 598 mm². It belongs to the Xeon 600 (Granite Rapids-WS) generation and is designed for the server and workstation market. The AMD Ryzen 9 9950X3D uses the Zen 5 architecture, built by TSMC on a 4 nm process, with a die size of two 70.6 mm² chiplets. It is part of the 9000 series and the Ryzen 9 (Zen 5 (Granite Ridge)) generation, targeting the desktop segment.

A critical difference lies in PCIe lane allocation. The Intel Xeon 638 offers Gen 5 with 80 CPU-only lanes, while the AMD Ryzen 9 9950X3D offers Gen 5 with 24 CPU-only lanes. The Xeon also has integrated graphics listed as N/A, while the Ryzen 9 9950X3D includes Radeon Graphics. The AMD part has a transistor count of 16,630 million, while the Intel part has no recorded transistor count in the database.

Specification Differences

The two CPUs differ in several key specification fields. The Intel Xeon 638 has a base clock of 3.20 GHz and a boost clock of 4.80 GHz, while the AMD Ryzen 9 9950X3D operates at 4.30 GHz base and 5.70 GHz boost. The TDP is 180 watts for the Intel part and 170 watts for the AMD part. The Intel Xeon 638 uses the Intel Socket 4710, whereas the AMD Ryzen 9 9950X3D uses the AMD Socket AM5.

Memory bus widths provide a stark contrast, with the Intel part supporting quad-channel DDR5 and achieving a bandwidth of 204.8 GB/s, while the AMD part supports dual-channel DDR5 with a bandwidth of 89.6 GB/s. The Intel Xeon 638 has a larger die size of 598 mm², compared to the AMD's two 70.6 mm² chiplets. The cache hierarchy differs, with Intel offering 112 KB L1 and 2 MB L2 per core, and 72 MB shared L3, while AMD offers 80 KB L1 and 1 MB L2 per core, and 128 MB of L3. The PCIe lane count is also a major difference, with Intel providing 80 Gen 5 lanes, and AMD providing 24.

The release dates differ, with the AMD Ryzen 9 9950X3D releasing on 2025-01-05, while the Intel Xeon 638 is released on 2026-02-01. The Intel part has a launch MSRP of $899, and the AMD part has a launch MSRP of $699. The Intel Xeon 638 has a part number of SA2DN, while the AMD Ryzen 9 9950X3D has a part number of 100-000000719. Both have unlocked multipliers, but the Intel Xeon 638 is a Server/Workstation part, while the AMD is a Desktop part.

The Verdict

The data suggests a straightforward choice based on workload. If the priority is single-threaded performance in Cinebench R15 and R23, the Intel Xeon 638 is the clear winner, with a staggering 195% higher score in R23 single-core and a 91.7% higher score in R15 single-core. It also wins the Cinebench R23 multi-core test by 12.3% despite the AMD part's higher base clock.

For almost every other measured scenario, the AMD Ryzen 9 9950X3D is the better performer. The AMD chip leads in the PassMark suite across the board, including a 37.8% lead in prime number processing, a 24% lead in integer math, and a 20.8% lead in multithreaded performance. It also has a higher single-threaded PassMark score, a 22.5% improvement. The Ryzen 9 9950X3D also offers a larger L3 cache, higher boost clock, and a lower TDP, making it a more efficient part.

The Intel Xeon 638's redeeming qualities, aside from its Cinebench single-core dominance, are its massive PCIe lane count and quad-channel memory bandwidth, which are features designed for server and workstation expansion. The choice comes down to the specific workload: for raw scientific or rendering tasks that rely on Cinebench, the Intel part wins its unique tests. For the vast majority of other computational tasks, the AMD Ryzen 9 9950X3D is the more capable processor, with its 12 wins out of 15 head-to-head benchmarks.