Intel Atom x7835RE vs Intel Xeon E3-1565L v5 Comparison

The Intel Xeon E3-1565L v5 and Intel Atom x7835RE occupy opposite ends of the Intel spectrum, yet their benchmark results reveal a surprisingly competitive matchup. The Xeon is a legacy 14 nm server part, while the Atom is a modern 10 nm mobile processor. The recorded data shows a clear split: the Xeon dominates in most legacy and single-threaded workloads, while the Atom wins in specific math-heavy and encryption tasks.

Head-to-Head Benchmarks

The Xeon E3-1565L v5 wins 14 of the 17 recorded benchmark comparisons, but the margins vary enormously. The most decisive Xeon victory comes in PassMark's extended instructions test, where it scores 6031 against the Atom's 3617, a 66.7% advantage. This suggests the Xeon has a significantly stronger implementation of advanced instruction sets, which is critical for workloads like cryptography and certain media codecs.

Almost as impressive is the Xeon's performance in PassMark find prime numbers. The Xeon scores 43, while the Atom manages just 23, an 87% delta. This is a huge difference in a pure integer workload that stresses CPU arithmetic logic. The Xeon also wins the PassMark physics test by a wide margin: 794 versus 500, a 58.8% improvement.

The single-threaded PassMark test shows another clear Xeon victory. The Xeon scores 1970, while the Atom scores 1599, a 23.2% advantage. This is one of the largest deltas in the head-to-head data. The Xeon also leads in data compression, scoring 94771 against the Atom's 76736, a 23.5% edge. In random string sorting, the Xeon leads by 13.4% (11543 vs 10180). The Cinebench results are all Xeon wins, but the margins are narrower. In Cinebench R15 multicore, the Xeon scores 627 vs 609, a 3% lead. The single-core scores in R15 are 88 vs 85, a 3.5% lead. In R23, the Xeon wins multicore by 2.9% (6226 vs 6051) and single-core by 2.9% (879 vs 854).

The Atom's three wins are substantial. In PassMark data encryption, the Atom crushes the Xeon: 5579 versus 2314, a delta of 58.5% in the Atom's favor. This is a massive reversal and indicates a hardware-accelerated AES engine. The Atom also wins PassMark floating point math, scoring 16236 against the Xeon's 14547, a 10.4% advantage. Finally, in integer math, the Atom leads with 26623 versus 23335, a 12.4% win. These results indicate the Atom has a more powerful vector math unit per clock, despite its lower base clock.

The average benchmark scores place the Xeon at 10320, and the Atom at 9430. This puts the Xeon in the 66th percentile of all CPUs, while the Atom sits at the 65th percentile. The Xeon's nearest rivals include the Intel Xeon Gold 6338N (score 10347, 0.3% apart) and the Xeon W-3175X (10369, 0.5% apart). The Atom's nearest rivals include the Intel Xeon Platinum 8180 (score 9406, 0.3% apart) and the AMD EPYC 7402P (9529, 1% apart). These figures show that despite their different architectures, both processors perform at a similar overall level when all benchmarks are averaged.

Architecture Differences

The most fundamental difference is the manufacturing process. The Xeon E3-1565L v5 is built on Intel's 14 nm node, while the Atom x7835RE uses the newer 10 nm node. The Xeon has a die size of 171 mm² and contains 2,300 million transistors. The Atom's transistor count and die size are not recorded in the database.

The core counts and memory topology differ. The Xeon has 4 cores and 8 threads, using Hyper-Threading. The Atom has 8 cores and 8 threads, which means it lacks multi-threading. The Xeon uses the Skylake architecture, specifically the Skylake-H codename. The Atom uses the Amston Lake architecture, which leverages the Gracemont core design.

Cache layout is another key difference. The Xeon has 64 KB of L1 cache per core and 256 KB of L2 per core. The Atom has 96 KB of L1 per core, but only 2 MB of L2 per module (with two cores per module). The Xeon has 8 MB of shared L3 cache, while the Atom has 6 MB of shared L3. This means the Xeon has more total cache but the Atom has a larger L1.

Memory support is completely different. The Xeon supports DDR3 and DDR4, while the Atom supports DDR4 and DDR5. The Xeon has a dual-channel memory bus with a theoretical bandwidth of 34.1 GB/s. The Atom has a single-channel memory bus with a slightly higher theoretical bandwidth of 38.4 GB/s. This is unusual, as the single-channel Atom can move more theoretical data per clock than the dual-channel Xeon, likely due to the faster DDR5 support.

The Xeon supports ECC memory, which is a requirement for many server workloads. The Atom does not. The Xeon offers 16 PCIe Gen 3 lanes from the CPU, while the Atom offers 9 Gen 3 lanes. The Xeon's integrated graphics are Iris Pro Graphics P580, while the Atom has UHD Graphics 32EU. These are both integrated solutions but with different capabilities. The Xeon is a server/workstation part, while the Atom is classified as a mobile part.

Where Each One Wins

The Xeon E3-1565 v5 has a clear advantage in single-threaded performance. The PassMark single-thread score shows a 23.2% lead over the Atom. This is further supported by the Cinebench R15 and R20 single-core results, where the Xeon leads by 3.5% and 3.1% respectively. The Xeon's higher base clock (2.50 GHz) and boost clock (3.50 GHz) likely contribute to this, though the Atom has a slightly higher boost of 3.60 GHz. The Xeon's advantage in physics (58.8%) and extended instructions (66.7%) makes it a better choice for simulation and scientific workloads.

The Xeon also wins in data compression, leading by 23.5%. This suggests it is more efficient at tasks that require fast, repetitive memory access and integer operations. The random string sorting test, which the Xeon wins by 13.4%, also indicates a strength in sorting and text-processing tasks.

The Atom x7835- has a decisive win in data encryption, where it is 58.5% faster than the Xeon. This is a massive difference and indicates the Atom has dedicated hardware for AES encryption, which the Xeon lacks. For workloads that involve HTTPS, VPN, or disk encryption, the Atom would be significantly faster.

The Atom wins in floating point math by 10.4% and integer math by 12.4%. This shows that the Atom's Gracemont cores, despite their low 1.30 GHz base clock, are capable of higher absolute math throughput than the Skylake cores in the Xeon. This is likely due to the much newer architecture and its ability to execute more instructions per clock cycle. For tasks like financial modeling or scientific simulations that rely heavily on math, the Atom is the stronger performer.

Specification Differences

The specification table shows the most obvious differences:

• Cores: Xeon 4, Atom 8
• Threads: Xeon 8, Atom 8
• Base Clock: Xeon 2.50 GHz, Atom 1.30 GHz
• Boost Clock: Xeon 3.50 GHz, Atom 3.60 GHz
• TDP: Xeon 35 W, Atom 12 W
• Socket: Xeon BGA 1440, Atom BGA 1264
• Process Node: Xeon 14 nm, Atom 10 nm
• L1 Cache: Xeon 64 KB per core, Atom 96 KB per core
• L2 Cache: Xeon 256 KB per core, Atom 2 MB per module
• L3 Cache: Xeon 8 MB shared, Atom 6 MB shared
• Memory Support: Xeon DDR3/DDR4, Atom DDR4/DDR5
• Memory Bus: Xeon Dual-channel, Atom Single-channel
• Memory Bandwidth: Xeon 34.1 GB/s, Atom 38.4 GB/s
• ECC Memory: Xeon Yes, Atom No
• PCIe Lanes: Xeon 16, Atom 12
• Integrated Graphics: Xeon Iris Pro P580, Atom UHD 330
• Market Segment: Xeon Server/Workstation, Atom Mobile
• Production Status: Xeon End-of-life, Atom Active
• Release Date: Xeon 2016-05-30, Atom 2024-04-07
• Launch MSRP: Xeon $417, Atom $127

FAQ

Q: Which processor is faster for single-threaded tasks?

A: The Intel Xeon E3-1565 v5 is significantly faster. It scores 1970 in the PassMark single-thread test, compared to the Atom's 1599, a 23.2% advantage. It also leads in Cinebench R23 single-core by 2.9%.

Q: Does the Atom x7835- have any major advantage over the Xeon?

A: Yes, in data encryption. The Atom scores 5579 in PassMark's data encryption test, while the Xeon scores 2314. The Atom is 58.5% faster in this specific workload.

Q: Which processor has more cores and threads?

A: The Atom has 8 cores and 8 threads, while the Xeon has 4 cores and 8 threads. The Xeon uses Hyper-Threading to achieve 8 threads from 4 cores.

Q: What is the difference in power consumption?

A: The Atom has a TDP of 12 W, while the Xeon has a TDP of 35 W. The Atom is significantly more power-efficient, which is typical for a mobile processor.

Q: Which processor supports ECC memory?

A: The Xeon E3-1565 v5 supports ECC memory, while the Atom x7835- does not. This makes the Xeon more suitable for error-sensitive server workloads.

Q: Which processor has a better memory bandwidth?

A: The Atom has a slightly higher theoretical memory bandwidth of 38.4 GB/s, despite using a single-channel bus. The Xeon has a dual-channel bus with a bandwidth of 34.1 GB/s. The Atom's support for DDR5 memory contributes to this.

Q: Which processor is better for math-heavy workloads?

A: The Atom wins in PassMark integer math (26623 vs 23335) and floating point math (16236 vs 14547). The Atom is 12.4% better in integer math and 10.4% better in floating point math.

Q: What is the difference in the number of PCIe lanes?

A: The Xeon provides 16 PCIe Gen 3 lanes from the CPU, while the Atom provides 12 Gen 3 lanes. This gives the Xeon more room for high-speed expansion cards.

The Verdict

The database paints a clear picture. For users who prioritize single-threaded performance, data compression, physics, and extended instruction workloads, the Intel Xeon E3-1565 v5 is the stronger choice. Its 23.2% lead in PassMark single-thread and 23.5% lead in data compression makes it a better fit for tasks like legacy application support, compression tools, and single-threaded server scripts. The Xeon's support for ECC memory makes it a sensible option for a low-power server environment where data integrity is critical.

However, the Atom x7835- is the better option for workloads that leverage modern encryption or heavy math. Its 58.5% advantage in data encryption is a decisive factor for tasks that handle secure connections or encrypted storage. The Atom also wins in integer and floating point math, making it a stronger candidate for scientific simulations and financial calculations that rely on pure mathematical throughput.

The Atom's active production status, 10 nm process, and 12 W TDP make it a modern, power-efficient choice for mobile or embedded systems. The Xeon is end-of-life and has a higher 35 W TDP. For new designs where power efficiency is paramount, the Atom is the obvious choice. For legacy server compatibility with ECC support and stronger single-threaded performance, the Xeon remains viable. The data shows no universal winner, only a clear split based on workload priorities.