Intel Core i9-9900X vs Intel Xeon E5-2699A v4 Comparison

The Intel Core i9-9900X and the Intel Xeon E5-2699A v4 represent two fundamentally different approaches to high-core-count computing, and the benchmark data shows a clear split. The i9-9900X wins 7 of 8 head-to-head tests, including every Cinebench test, while the Xeon E5-2699A v4 counters with a decisive 10% victory in Geekbench multi-core. The i9-9900X is the stronger all-around performer for most workloads, but the Xeon’s raw thread count makes it a specialist for heavily parallel tasks.

FAQ

Q: Which processor has more cores and threads?

A: The Intel Xeon E5-2699A v4 has 22 cores and 44 threads, compared to the Intel Core i9-9900X’s 10 cores and 20 threads.

Q: Who wins in single-core performance?

A: The Intel Core i9-9900X wins every single-core benchmark. The largest margin is in Geekbench single-core, where it scores 1429 versus 1020, a 40.1% advantage.

Q: In which benchmark does the Xeon E5-2699A v4 outperform the i9-9900X?

A: The Xeon wins only the Geekbench multi-core test, scoring 10118 against 9109, a 10% lead.

Q: Do both processors support the same memory configuration?

A: Both support DDR4 memory with a quad-channel memory bus. The i9-9900X has a theoretical memory bandwidth of 85.3 GB/s, while the Xeon E5-2699A v4 has 76.8 GB/s.

Q: What is the difference in their L3 cache sizes?

A: The Xeon E5-2699A v4 has a much larger 55 MB shared L3 cache, whereas the i9-9900X has 19.25 MB shared.

Q: Which processor has a higher base clock speed?

A: The Intel Core i9-9900X has a base clock of 3.50 GHz, which is higher than the Xeon E5-2699A v4’s 2.40 GHz.

Architecture Differences

The two CPUs come from different Intel architectures built on the same 14 nm process node. The Intel Core i9-9900X uses the Skylake architecture, specifically the Skylake-X codename, and belongs to the Core i9 X-Series 9th Gen family. The Intel Xeon E5-2699A v4 uses the Broadwell architecture, specifically Broadwell-EP, and belongs to the Xeon E5 family.

Core and thread counts present the most obvious architectural divergence. The Xeon packs 22 cores and 44 threads, more than double the i9-9900X’s 10 cores and 20 threads. This core advantage is partly offset by the Xeon’s lower clocks: the Xeon has a 2.40 GHz base and 3.60 GHz boost, while the i9-9900X runs at 3.50 GHz base and 4.50 GHz boost. The higher boost clock is a key reason the i9 wins all single-core tests.

Cache hierarchies differ substantially. The i9-9900X has 64 KB of L1 and 1 MB of L2 per core, with 19.25 MB of shared L3. The Xeon E5-2699A v4 has the same 64 KB L1 per core, but only 256 KB L2 per core, and a much larger 55 MB shared L3. The Xeon also has a larger physical footprint: its die size is 456 mm² with 7,200 million transistors, whereas the i9-9900X’s die size and transistor count are not listed in the data.

Memory support is similar in type, with both using DDR4 and a quad-channel memory bus. However, the i9-9900X has a higher theoretical memory bandwidth of 85.3 GB/s versus 76.8 GB/s for the Xeon. The Xeon supports ECC memory, while the i9-9900X does not. PCIe connectivity also differs: the i9-9900X provides 44 Gen 3 lanes, while the Xeon provides 40 Gen 3 lanes. The i9-9900X has an unlocked multiplier, whereas the Xeon’s multiplier is locked. Sockets are incompatible: the i9-9900X uses Intel Socket 2066, and the Xeon uses Intel Socket 2011-3.

Head-to-Head Benchmarks

The benchmark data shows a consistent pattern: the i9-9900X dominates in Cinebench, and the Xeon wins only in Geekbench multi-core. Starting with Cinebench R15 multi-core, the i9-9900X scores 1851 against the Xeon’s 1796, a 3.1% lead. In Cinebench R15 single-core, the i9 scores 261 versus 253, a 3.2% margin. The story repeats in Cinebench R20: multi-core shows 7713 for the i9 and 7486 for the Xeon, a 3% difference, while single-core shows 1088 versus 1056, also 3%. Cinebench R23 continues the trend, with the i9 winning multi-core 18365 to 17826 (3% lead) and single-core 2592 to 2516 (3% lead).

The Geekbench results break the pattern. In Geekbench single-core, the i9-9900X wins decisively with a score of 1429 versus 1020, a massive 40.1% advantage. However, in Geekbench multi-core, the Xeon E5-2699A v4 takes the win with 10118 against 9109, a 10% margin. This split suggests that the Xeon’s 22 cores provide a real advantage in certain multi-threaded workloads, but the i9-9900X’s superior single-thread performance and higher clocks keep it ahead in most other tests.

The average benchmark scores reflect this overall balance. The i9-9900X has an average benchmark score of 5301, placing it in the 60th percentile of all CPUs. The Xeon E5-2699A v4 has an average score of 5259, also in the 60th percentile. The nearest rivals for the i9-9900X include the AMD Ryzen Threadripper 1920X with an average score of 5306 (0.1% higher) and the Intel Core i9-10900KF with 5316 (0.3% higher). The Xeon’s nearest rivals include the Intel Core i5-14401E at 5253 (0.1% lower) and the Intel Core i9-10850K at 5240 (0.4% lower). Interestingly, the two CPUs in this comparison are listed as rivals to each other: the Xeon appears in the i9-9900X’s rival list with a delta of -0.8%, and the i9-9900X appears in the Xeon’s list with the same -0.8% delta.

Specification Differences

The specification sheet shows several clear differences beyond the obvious core count. The i9-9900X has a base clock of 3.50 GHz and boost clock of 4.50 GHz, while the Xeon E5-2699A v4 runs at 2.40 GHz base and 3.60 GHz boost. The i9-9900X has a TDP of 165 watts, higher than the Xeon’s 145 watts.

Memory bandwidth differs, with the i9-9900X listing 85.3 GB/s and the Xeon listing 76.8 GB/s. ECC memory support is exclusive to the Xeon. PCIe lane counts are 44 for the i9-9900X and 40 for the Xeon. The sockets are different, with the i9-9900X on Intel Socket 2066 and the Xeon on Intel Socket 2011-3.

The cache configurations are notably different. The i9-9900X has 1 MB L2 per core and 19.25 MB shared L3, while the Xeon has 256 KB L2 per core and 55 MB shared L3. Both share the same 64 KB L1 per core. The Xeon’s die size is listed as 456 mm² with 7,200 million transistors, while these figures are not provided for the i9-9900X.

The Xeon E5-2699A v4 was released on 2016-10-24, while the i9-9900X launched on 2018-10-18. The i9-9900X has an unlocked multiplier; the Xeon’s multiplier is locked. The launch MSRP for the i9-9900X is $989. The launch MSRP for the Xeon E5-2699A v4 is $4938.

Where Each One Wins

The Intel Core i9-9900X wins in scenarios that favor higher clock speeds and stronger single-thread performance. Its 40.1% lead in Geekbench single-core and consistent 3% edges across all Cinebench tests make it the clear choice for applications that are not perfectly scaled across many cores. The higher boost clock of 4.50 GHz and larger L2 cache per core contribute to these wins. This CPU is better suited for general desktop workloads, older software that relies on fewer threads, and tasks where per-core performance is the bottleneck.

The Intel Xeon E5-2699A v4 wins in the Geekbench multi-core test, scoring 10% higher than the i9-9900X. This result points to workloads that can fully utilize 22 cores and 44 threads, where the Xeon’s core advantage overcomes its lower clocks. The Xeon’s 55 MB shared L3 cache and ECC memory support also make it attractive for memory-intensive and reliability-sensitive server-style workloads, though the benchmark data only directly confirms the multi-core performance edge.

The i9-9900X also wins on memory bandwidth, with 85.3 GB/s versus 76.8 GB/s, and offers more PCIe lanes at 44 versus 40. These features support high-bandwidth peripherals and multi-GPU configurations. However, the Xeon’s ECC memory support is a feature the i9-9900X lacks entirely.

The Verdict

The data points to a clear split decision. The Intel Core i9-9900X is the better processor for the majority of benchmark scenarios, winning 7 out of 8 head-to-head tests. Its single-core performance is exceptional, with a 40.1% lead in Geekbench single-core, and it maintains a 3% advantage in every Cinebench test. The i9-9900X also offers higher memory bandwidth and more PCIe lanes. This makes it the pragmatic choice for users who need strong all-around performance, including gaming, content creation, and productivity tasks that benefit from high clock speeds.

The Intel Xeon E5-2699A v4 is the specialist. Its single Geekbench multi-core win, with a 10% margin, demonstrates that its 22 cores and 44 threads deliver real results in heavily parallel workloads. The Xeon also provides ECC memory support and a significantly larger 55 MB L3 cache. For users running applications that scale perfectly across many threads, the Xeon’s multi-core performance is superior. However, its lower clocks and weaker single-core scores mean it falls behind in most other tests.

The average benchmark scores are nearly identical, with the i9-9900X at 5301 and the Xeon at 5259, both sitting in the 60th percentile. This near-parity in overall scoring, combined with the 7-1 split in individual tests, suggests that the i9-9900X offers broader applicability. The Xeon is the right choice only when its specific advantages—core count, ECC support, and large L3 cache—are critical. For every other scenario, the i9-9900X’s higher clocks and superior single-thread performance make it the recommended processor.