CPU Comparison

The Intel Xeon E5-1607 v3 and the Intel Core i3-8121U occupy opposite corners of the hardware spectrum: a 140 W server/workstation part from the Haswell generation against a 15 W mobile chip built on Cannon Lake. Despite their differences in lineage, the aggregate benchmark data places them within a hair of each other, the Xeon averages 1212 points, the Core i3 averages 1209, a difference of roughly 0.2%. Yet the head-to-head results tell a more decisive story, with the Xeon winning every single benchmark by a margin of about 15%. The data suggests that raw architectural age is less important than core count and power envelope when comparing these two specific SKUs.

Head-to-Head Benchmarks

The Xeon E5-1607 v3 sweeps all six shared Cinebench tests, and the margins are remarkably consistent. In Cinebench R15 multi-core, the Xeon scores 422 against the Core i3's 366, a 15.3% advantage. The single-core test in R15 shows a similar gap: 59 to 51, a 15.7% win for the Xeon. This consistency continues into R20, where the Xeon posts 1761 multi-core and 248 single-core, versus 1527 and 215 for the i3, again 15.3% in both. The R23 results follow the pattern: 4193 to 3637 multi-core and 591 to 513 single-core, with deltas of 15.3% and 15.2% respectively.

The uniformity of these margins is striking. Whether the workload is heavily threaded or purely single-core, the Xeon's lead stays pinned near 15%. This suggests the difference is not about scaling efficiency or turbo behavior, but rather a fundamental per-clock performance gap. The Xeon's base clock is 3.10 GHz, while the Core i3 has a 2.20 GHz base and a 3.20 GHz boost, yet the Xeon still wins single-core tests by 15%. That implies the Haswell architecture, at a similar or lower clock, is delivering more instructions per cycle than the Cannon Lake part in these specific workloads, or that the mobile chip's thermal constraints prevent it from sustaining its boost clock.

The Core i3-8121U does have one benchmark the Xeon lacks: Geekbench. It scores 2215 multi-core and 1149 single-core, but there is no corresponding Geekbench result for the Xeon in the data, so a direct comparison is impossible. What can be said is that the i3's average score of 1209 places it in the 34th percentile of all CPUs, identical to the Xeon's percentile. The two chips are, on average, statistical twins despite the Xeon's clean sweep in Cinebench.

FAQ

Q: Which processor wins more benchmarks in the head-to-head comparison?

A: The Intel Xeon E5-1607 v3 wins all six shared Cinebench tests. The Core i3-8121U has zero head-to-head wins, though it does have two Geekbench results that have no Xeon counterpart.

Q: How large is the performance gap in multi-core workloads?

A: The Xeon leads by 15.3% in Cinebench R15, R20, and R23 multi-core tests. The scores are 422 vs 366, 1761 vs 1527, and 4193 vs 3637 respectively.

Q: Does the Core i3's higher boost clock help it win single-core tests?

A: No. Despite the i3's 3.20 GHz boost clock versus the Xeon's fixed 3.10 GHz, the Xeon wins single-core Cinebench tests by 15.2–15.7%. The i3's single-core scores are 51 in R15, 215 in R20, and 513 in R23.

Q: Are the two chips close in overall average benchmark score?

A: Yes, extremely close. The Xeon averages 1212 points, and the Core i3 averages 1209 points, a difference of only 0.2%. Both sit in the 34th percentile of all CPUs.

Q: What are the nearest rivals for each chip according to the data?

A: The Xeon's nearest rival is the Core i3-7300T and Xeon E5645, both averaging 1211 with a 0.1% delta. The Core i3-8121U's nearest rival is the Xeon D-1520 at 1209 with a 0% delta.

Q: Do the processors share any benchmark where the i3 comes close?

A: The closest margin is in Cinebench R23 multi-core, where the Xeon leads by 15.2%. No shared test shows a smaller gap than 15.2%.

The Verdict

The data points to a clear, if counterintuitive, conclusion: the older, higher-power Xeon E5-1607 v3 is the faster processor in every measurable shared workload. The 15% advantage is consistent across single-core and multi-core tests, indicating a per-thread performance edge that the Core i3's higher boost clock cannot overcome. The i3-8121U's only consolation is its Geekbench results, 2215 multi-core and 1149 single-core, but without a Xeon score for that test, it cannot claim a win.

For buyers prioritizing raw compute performance in Cinebench-style rendering tasks, the Xeon is the choice. It offers 4 cores and 4 threads, 10 MB of shared L3 cache, and quad-channel DDR4 memory with 59.7 GB/s of bandwidth. The Core i3 offers 2 cores and 4 threads, 4 MB of L3 cache, and dual-channel memory at 38.4 GB/s. The Xeon's 140 W TDP and Socket 2011-3 platform demand a serious motherboard and cooling solution, whereas the i3's 15 W TDP in BGA 1440 is designed for compact, power-efficient mobile systems. The Xeon also supports ECC memory, a feature absent from the i3.

That said, the average benchmark scores are nearly identical, 1212 vs 1209, which means in a broader mix of applications, the two might perform similarly overall. The Xeon's wins are specific to Cinebench's rendering engine. The i3's Geekbench scores suggest it holds its own in other types of workloads, though the lack of a direct Xeon comparison prevents a definitive statement.

Specification Differences

The most obvious difference is core count: the Xeon has 4 cores and 4 threads, while the Core i3 has 2 cores and 4 threads. Base clocks differ significantly, with the Xeon at 3.10 GHz and the i3 at 2.20 GHz, though the i3 adds a 3.20 GHz boost clock that the Xeon lacks entirely. TDP is a chasm, 140 W for the Xeon versus 15 W for the i3.

Memory configuration also splits them: the Xeon uses quad-channel DDR4 with 59.7 GB/s bandwidth, while the i3 uses dual-channel DDR4 at 38.4 GB/s. ECC memory is supported on the Xeon but not the i3. PCIe lanes differ as well, with the Xeon offering 40 lanes and the i3 offering 16, both Gen 3. L3 cache is 10 MB shared on the Xeon versus 4 MB shared on the i3. The sockets are incompatible: Socket 2011-3 for the Xeon, BGA 1440 for the i3. Neither has integrated graphics, and neither has an unlocked multiplier.

Architecture Differences

The Xeon E5-1607 v3 is built on Intel's 22 nm process with 2,600 million transistors on a 356 mm² die. It uses the Haswell architecture, specifically Haswell-EP, and belongs to the Xeon E5 generation. The Core i3-8121U is a 10 nm part with a 70.52 mm² die size; transistor count is not listed. It uses the Cannon Lake architecture, though Intel labels its generation as "Core i3 (Kaby Lake-U Refresh)", a naming inconsistency in the data. The codename for the i3 is simply Cannon Lake.

The process node difference is substantial: 22 nm for the Xeon versus 10 nm for the i3, a generational leap in manufacturing. Yet the Xeon's larger die and higher transistor count give it more physical resources for caching and memory control. The Xeon's 10 MB L3 cache is 2.5 times larger than the i3's 4 MB. The memory controller is also wider on the Xeon (quad-channel vs dual-channel), which directly explains its 55% higher memory bandwidth figure of 59.7 GB/s versus 38.4 GB/s.

The Xeon is a server/workstation part released in September 2014, while the i3 is a mobile part released in May 2018. Both are end-of-life. The Xeon's market segment explains its ECC support and 40 PCIe lanes, while the i3's mobile segment explains its 15 W TDP and BGA packaging. The i3's boost clock of 3.20 GHz is its only clock advantage, but the benchmark data shows it does not translate into Cinebench wins.

Where Each One Wins

The Xeon E5-1607 v3 wins every shared benchmark, making it the clear choice for Cinebench-style rendering workloads. Its 15.3% multi-core lead in R15, R20, and R23 means it will render frames or scenes faster in that specific software. The single-core leads of 15.2–15.7% also suggest better responsiveness in lightly threaded tasks within Cinebench. The Xeon's quad-channel memory and 10 MB cache likely contribute to this stability across test versions.

The Core i3-8121U's wins are not in the head-to-head data but in its own benchmark portfolio. Its Geekbench scores, 2215 multi-core and 1149 single-core, are the only results where it can claim any performance identity. For users running Geekbench-style workloads or needing a 15 W mobile processor that fits in BGA 1440, the i3 is the only option of the two. Its dual-channel memory and smaller cache are adequate for its intended laptop segment, and its 10 nm process means it generates far less heat than the Xeon's 140 W design.

In practical terms, the Xeon wins where power and cooling are available: workstation towers and servers. The i3 wins where power efficiency and compactness are paramount: thin laptops and embedded mobile systems. There is no overlap in sockets, so the choice is dictated by platform before performance. If you have a Socket 2011-3 board, the Xeon is the superior performer in Cinebench. If you have a BGA 1440 board, the i3 is your only option, and its average score of 1209 puts it in the same percentile as the Xeon despite its 15% disadvantage in rendering tests.