Intel Core i5-8305G vs Intel Xeon E3-1558L v5 Comparison

Head-to-Head Benchmarks

The benchmark data paints a clear picture: the Intel Xeon E3-1558L v5 wins every single head-to-head comparison in the database, taking all six recorded tests. The Core i5-8305G does not win a single benchmark in this matchup. The margin is consistent across the board, with the Xeon leading by roughly 12% in both single-threaded and multi-threaded workloads.

In Cinebench R15 multi-core, the Xeon scores 655 against 578 for the Core i5, a delta of -11.8% for the i5. The single-core R15 result shows the same story: 92 for the Xeon versus 81 for the i5, a 12% gap. These early tests set the tone for the entire comparison.

Cinebench R20 follows the identical pattern. The Xeon posts 2733 multi-core versus 2410 for the i5, and 385 single-core versus 340, both with deltas around -11.7% to -11.8%. The most recent Cinebench R23 test repeats the script: 6508 multi-core for the Xeon against 5739 for the i5, and 918 single-core versus 810. Every delta in the head-to-head list sits between -11.7% and -12%, which points to a consistent architectural advantage rather than a workload-specific quirk.

The average benchmark score in the database reinforces this. The Xeon E3-1558L v5 averages 1882, while the i5-8305G averages 1831. That is a difference of roughly 2.7% in the Xeon's favor across the entire recorded benchmark set. The percentile rankings are close too: the Xeon sits at the 43rd percentile of all CPUs, while the i5 sits at the 42nd. Both are firmly mid-pack processors, but the Xeon is consistently ahead.

The Geekbench scores are only recorded for the i5-8305G in the database, with 3536 multi-core and 1150 single-core. There is no comparable Geekbench data listed for the Xeon, so any direct comparison there is impossible from the recorded facts. For the tests where both are measured, the Xeon simply leads every time.

Architecture Differences

Both processors are built on Intel's 14 nm process node, but their architectures differ significantly. The i5-8305G uses the Kaby Lake architecture, specifically the Kaby Lake G codename, and belongs to the Core i5 generation. The Xeon E3-1558L v5 uses the Skylake architecture, with the Skylake-H codename, and belongs to the Xeon E3 generation.

The Xeon has a larger shared L3 cache: 8 MB shared versus 6 MB shared for the i5. Both have the same per-core L1 and L2 cache allocation, with 64 KB per core for L1 and 256 KB per core for L2. The Xeon also carries additional documented specifications: 2,300 million transistors and a die size of 171 mm², while the i5 has no transistor count or die size listed in the database.

Several other differences appear in the specification data. The Xeon supports both DDR3 and DDR4 memory, while the i5 lists DDR4 only. The Xeon has a dual-channel memory bus and a recorded memory bandwidth of 34.1 GB/s, while the i5 has no memory bus or bandwidth figures in the database. The Xeon supports ECC memory, which is a key server and workstation feature, while the i5 does not.

The integrated graphics differ as well. The i5-8305G carries a Radeon RX Vega M GL, which is a discrete-class GPU on the package. The Xeon E3-1558L v5 uses Iris Pro Graphics P555. These are very different graphics solutions, and for workloads that lean on the iGPU, that difference matters. The Xeon has a PCIe specification listed as Gen 3 with 16 lanes from the CPU, while the i5 has no PCIe data recorded.

The sockets are also different: the i5 uses Intel BGA 2270, while the Xeon uses Intel BGA 1440. The Xeon is marked as end-of-life production status, while the i5 is listed as active. The Xeon launches earlier, with a release date in May 2016, while the i5 arrives in January 2018.

Where Each One Wins

The Xeon E3-1558L v5 wins every recorded benchmark, so the use-case split is straightforward. In multi-threaded workloads, the Xeon leads by 11.8% in Cinebench R15, R20, and R23. That includes rendering tasks and other heavily parallelized workloads. The single-threaded advantage is nearly identical, sitting at 12% in R15 and 11.8% in R20 and R23, so the Xeon also wins in lightly-threaded tasks like general desktop responsiveness and single-threaded application performance.

The Xeon also brings the ECC memory support, which the i5 lacks. That makes the Xeon the appropriate choice for builds where memory error correction is required, such as entry-level server or workstation configurations. The Xeon's support for both DDR3 and DDR4 memory gives it more flexibility in existing platforms, while the i5 is locked to DDR4.

The i5-8305G does have one advantage in the database: its integrated Radeon RX Vega M GL graphics. While there is no benchmark score for that GPU in the database, the presence of a Radeon Vega M GL part on a CPU package is intended for tasks that need more graphics performance than typical integrated graphics. For a mobile system that wants moderate gaming or GPU-accelerated workloads without a separate discrete GPU, the i5-8305G is the more sensible option. The Xeon's Iris Iris Pro Graphics P555 is a more basic integrated solution.

The i5 is also the only one of the two with a recorded Geekbench result, showing 3536 multi-core and 1150 single-core, but that is not a direct comparison. The i5 is also listed as a mobile part, while the Xeon is a server/workstation part. The i5's 65 W TDP versus the Xeon's 45 W TDP means the Xeon draws less power in the database listing, which matters for compact builds or thermal-constrained systems.

FAQ

Q: Which CPU wins the most benchmarks?

A: The Intel Xeon E3-1558L v5 wins all six head-to-head benchmark tests. The Intel Core i5-8305G wins none.

Q: How large is the single-core performance gap?

A: In Cinebench R15 single-core, the Xeon scores 92 versus 81 for the i5, a 12% lead. R20 shows 385 versus 340, and R23 shows 918 versus 810, both at -11.8% for the i5.

Q: Does the i5-8305G have better multi-threaded performance?

A: No. The Xeon leads by 11.8% in each multi-core Cinebench test, scoring 655 versus 578 in R15, 2733 versus 2410 in R20, and 6508 versus 5739 in R23.

Q: Do both CPUs support ECC memory?

A: No. The Xeon E3-1558L v5 supports ECC memory, while the i5-8305G does not.

Q: What are the cache differences between the two?

A: Both have the same per-core L1 and L2 sizes, but the Xeon has 8 MB shared L3 cache, versus 6 MB shared for the i5.

Q: Which CPU has more power efficiency?

A: The Xeon E3-1558L v5 has a 45 W TDP, while the i5-8305G has a 65 W TDP, so the Xeon is the lower-power part.

The Verdict

The database is unambiguous. Every recorded benchmark, from Cinebench R15 to R23, places the Intel Xeon E3-1558L v5 ahead of the Intel Core i5-8305G by roughly 12% across the board. The Xeon's average score of 1882 also beats the i5's average of 1831, and the Xeon sits at the 43rd percentile versus 42nd for the i5. For any user who cares about raw CPU compute, the Xeon is the superior choice.

The Xeon also adds ECC memory support, a larger 8 MB L3 cache, and a lower TDP of 45 W versus 65 W. It supports DDR3 and DDR4, giving it more memory compatibility. The i5-8305G has no wins in the data, no ECC, and a smaller cache. Its only unique feature is the Radeon RX Vega M GL integrated graphics, which matters if the workload relies on the GPU portion of the package.

For a server or workstation build that demands ECC and consistent multi-threaded performance, the Xeon E3-1558L v5 is the right pick. For a mobile system where the bundled Radeon RX Vega M GL is more valuable than raw CPU throughput, the i5-8305G is the reasonable alternative. The data does not support any other conclusion, the Xeon is faster, cooler, and more feature-rich for compute tasks. The i5-8305G only justifies itself when the built-in graphics matter more than the CPU benchmark scores.

Specification Differences

• Base Clock: The i5-8305G has a base clock of 2.80 GHz, the Xeon E3-1558L v5 has a base clock of 1900.00 GHz.
• Boost Clock: The i5-8305G boosts to 3.80 GHz, the Xeon boosts to 3.30 GHz.
• TDP: The i5-8305G lists 65 W, the Xeon lists 45 W.
• Socket: The i5-8305G uses Intel BGA 2270, the Xeon uses Intel BGA 1440.
• Architecture: The i5-8305G is Kaby Lake (Kaby Lake G), the Xeon is Skylake (Skylake-H).
• Generation: The i5-8305G is in the Core i5 (Kaby Lake-G) generation, the Xeon is in the Xeon E3 (Skylake-H) generation.
• Transistors: The Xeon records 2,300 million transistors, the i5 has no recorded transistor count.
• Die Size: The Xeon has a 171 mm² die size, the i5 has no recorded die size.
• L3 Cache: The i5-8305G has 6 MB shared, the Xeon has 8 MB shared.
• Memory Support: The i5-8305G supports DDR4 only, the Xeon supports DDR3 and DDR4.
• Memory Bus: Not listed for the i5, the Xeon uses dual-channel.
• Memory Bandwidth: Not listed for the i5, the Xeon has 34.1 GB/s.
• ECC Memory: The i5-8305G does not support ECC, the Xeon does.
• PCIe: Not listed for the i5, the Xeon uses Gen 3 with 16 lanes from the CPU.
• Integrated Graphics: The i5-8305G uses Radeon RX Vega M GL, the Xeon uses Iris Pro Graphics P555.
• Release Date: The i5-8305G was released on 2018-01-31, the Xeon on 2016-05-30.
• Production Status: The i5 is Active, the Xeon is End-of-life.
• Part Number: Not listed for the i5, the Xeon has part number SR2TU.
• Launch MSRP: The Xeon has a launch MSRP of $396, the i5 does not have one listed.