Intel Atom C5315 vs Intel Xeon X5550 Comparison

Head-to-Head Benchmarks

The Intel Xeon X5550 and Intel Atom C5315 are separated by a narrow but consistent margin across all five recorded Cinebench tests. The Xeon X5550 wins every head-to-head benchmark, but the largest delta is only 2.0%. In Cinebench R23 single-core, the Xeon scores 364 against the Atom's 357, a 2.0% advantage. The R20 single-core test shows the same 2.0% delta, with scores of 152 and 149 respectively. Multi-threaded workloads follow the same pattern: the Xeon leads R15 multi-core 259 to 255 (1.6% ahead), R20 multi-core 1083 to 1063 (1.9% ahead), and R23 multi-core 2580 to 2533 (1.9% ahead). No test shows the Atom pulling ahead, even in single-threaded scenarios where a newer process node might be expected to help.

These deltas are small enough that real-world application differences would likely be imperceptible. The recorded data indicates a virtual tie in raw rendering throughput, with the Xeon's edge stemming from its 8 threads versus the Atom's 4 threads. In the database, the Xeon X5550 carries an average benchmark score of 888, placing it at the 24th percentile of all CPUs. The Atom C5315 averages 871, sitting at the 23rd percentile. The Xeon's nearest rivals include the Intel Core i3-6100 at a 0% delta and the Intel Pentium G4560T at a 0.1% delta, meaning the Xeon is effectively level with those parts. The Atom's closest competitor is the AMD Athlon PRO 3045B, which is 0.1% faster, and the Intel Core i3-5157U, which is 0.7% faster. Both processors land in the lower quarter of the database, reinforcing that neither is a high-performance part by modern standards.

The Verdict

The data points to a straightforward conclusion: the Intel Xeon X5550 is the faster processor in every benchmark category recorded. It wins all five head-to-head tests, holds a higher average benchmark score (888 versus 871), and sits one percentile point higher (24th versus 23rd). However, the margins are razor-thin. A 1.6% to 2.0% advantage across Cinebench tests does not translate into a meaningful performance tier difference. The Xeon's 8 threads give it a structural edge in multi-threaded rendering, but the Atom's newer architecture nearly closes that gap. The Atom C5315, with its 38 W TDP, is the clear choice for power-constrained deployments, while the Xeon X5550, at 95 W TDP, suits scenarios where the slight performance lead matters more than energy draw. Buyers with existing Intel Socket 1366 platforms could justify the Xeon, while those building fresh, low-power systems would favor the Atom. The Atom also remains in active production, whereas the Xeon is end-of-life, which affects long-term availability and platform support.

Architecture Differences

The two CPUs come from opposite ends of Intel's design spectrum. The Intel Xeon X5550 uses the Nehalem architecture, specifically the Gainestown codename, built on a 45 nm process node. It integrates 731 million transistors on a 263 mm² die. The Atom C5315 uses the Tremont architecture under the Parker Ridge codename, fabricated on a 10 nm node. The process node difference is substantial: 45 nm versus 10 nm, which explains the Atom's dramatically lower power consumption despite similar performance.

Cache layouts differ significantly. The Xeon X5550 has 64 KB of L1 cache per core, 256 KB of L2 cache per core, and 8 MB of shared L3 cache. The Atom C5315 has 64 KB of L1 per core but moves to a larger 4.5 MB L2 cache per module, with no L3 cache at all. This cache structure reflects the Atom's design goals: lower latency access to frequently used data without the complexity of a shared L3 pool.

Memory support also diverges. The Xeon supports DDR3 memory over a triple-channel bus, while the Atom supports DDR4 over a dual-channel bus. The Atom's memory bandwidth is recorded at 38.4 GB/s, a figure not provided for the Xeon. PCIe connectivity differs too: the Xeon offers Gen 2, while the Atom provides Gen 3 with 8 lanes (CPU only). Both support ECC memory, which is expected for server-oriented parts. The Atom has no integrated graphics, and the Xeon likewise lists none.

Specification Differences

The recorded specifications show several areas where the two parts diverge. Clock speeds favor the Xeon: it has a base clock of 2.67 GHz and a boost clock of 3.07 GHz. The Atom has a base clock of 2.40 GHz and no boost clock listed. Thread counts differ as well: the Xeon offers 8 threads from 4 cores, while the Atom offers 4 threads from 4 cores. This gives the Xeon a 2x thread advantage in multi-threaded workloads.

Power draw is a major separator. The Xeon has a TDP of 95 W, while the Atom draws only 38 W. The Atom's power efficiency is the standout feature here. Sockets are incompatible: the Xeon uses Intel Socket 1366, while the Atom uses Intel BGA 2106. Process nodes differ as noted: 45 nm versus 10 nm. The release dates are far apart, with the Xeon launching in 2009 and the Atom in 2022. Production status also differs: the Xeon is end-of-life, the Atom is active. The Atom has a launch MSRP of $213, while the Xeon has no launch MSRP recorded. The Atom's part number is SRL3Y, and the Xeon's is SLBF5.

FAQ

Q: Which processor is faster in single-core Cinebench R23?

A: The Intel Xeon X5550 scores 364 versus the Intel Atom C5315's 357, a 2.0% advantage for the Xeon.

Q: Does the Atom C5315 win any benchmark against the Xeon X5550?

A: No. The recorded head-to-head results show the Xeon winning all five Cinebench tests, with deltas ranging from 1.6% to 2.0%.

Q: What is the TDP difference between the two?

A: The Xeon X5550 has a TDP of 95 W, while the Atom C5315 has a TDP of 38 W, making the Atom significantly more power-efficient.

Q: Do both processors support ECC memory?

A: Yes, both the Xeon X5550 and the Atom C5315 have ECC memory support.

Q: What memory types do they use?

A: The Xeon X5550 uses DDR3 over a triple-channel bus, while the Atom C5315 uses DDR4 over a dual-channel bus.

Q: Which processor has more threads?

A: The Xeon X5550 has 8 threads from 4 cores, while the Atom C5315 has 4 threads from 4 cores.

Q: What is the average benchmark score for each?

A: The Xeon X5550 averages 888 points, and the Atom C5315 averages 871 points.

Where Each One Wins

The Intel Xeon X5550 wins in raw performance across every recorded benchmark, but only by a small margin. Its 8 threads give it a measurable edge in multi-threaded Cinebench workloads, and its single-core scores are also higher. The Xeon's 24th percentile placement and average score of 888 put it just ahead of the Atom's 23rd percentile and 871 average. For users running heavily threaded server workloads where every point of Cinebench score counts, the Xeon is the pick from the data. Its 95 W TDP is high, but for a machine that stays plugged in and runs sustained workloads, the performance lead, however modest, is consistent.

The Intel Atom C5315 wins in power efficiency, platform longevity, and memory technology. At 38 W, it draws less than half the power of the Xeon, making it the obvious choice for always-on systems, edge devices, or any deployment where heat and electricity costs dominate. The Atom supports DDR4 memory and PCIe Gen 3, newer standards than the Xeon's DDR3 and Gen 2. Its 10 nm process node is generations ahead of the Xeon's 45 nm node. The Atom is also in active production, while the Xeon is end-of-life, so the Atom offers a forward-looking platform. Its launch MSRP of $213 provides a reference point for procurement, though the Xeon's lack of a recorded MSRP prevents a direct cost comparison. For new builds, the Atom's socket (BGA 2106) and active status make it the safer investment despite the slight performance deficit. The Xeon's 8 MB of shared L3 cache could benefit workloads with large working sets, but the Atom's 4.5 MB L2 per module serves its target workloads adequately. In summary, the data shows the Xeon for maximum throughput and the Atom for efficiency and modern platform features.