AMD Athlon X4 845 vs Intel Xeon E5-1603 v3 Comparison

Head-to-Head Benchmarks

The recorded data paints a consistently clear picture: the Intel Xeon E5-1603 v3 wins every single head-to-head benchmark in the database. Out of five recorded Cinebench tests, the Xeon takes all five, with the AMD Athlon X4 845 trailing by a remarkably uniform margin. The deltas are tightly clustered, ranging from -15.2% to -15.6% across all tests, which suggests a steady, architectural performance gap rather than a workload-specific quirk.

In Cinebench R15 multi-core, the Xeon scores 382 against the Athlon's 324, a delta of -15.2%. That pattern repeats in Cinebench R20 multi-core, where the Xeon posts 1595 versus the Athlon's 1350, a -15.4% gap. The single-core results tell the same story. In Cinebench R20 single-core, the Xeon leads 225 to 190, a -15.6% difference, and in R23 single-core, the Xeon's 536 beats the Athlon's 453 by -15.5%. The largest single delta in the set is that R20 single-core result, but the spread across all tests is only 0.4 percentage points, so no benchmark category favors the AMD part.

The consistency of the margin is the key takeaway. This is not a case where one chip excels in threaded workloads while the other wins in lightly threaded ones. The Xeon's advantage is essentially flat, hovering around 15% in every test. The Athlon's higher clock speeds do not translate into any single-core win, which indicates that the Xeon's per-core efficiency, despite its lower base clock, is sufficient to overcome the frequency deficit.

For context, both processors sit at the 31st percentile among all CPUs in the database. Their average benchmark scores are also very close: the Athlon averages 1106, while the Xeon averages 1098. The nearest rivals for each chip underscore how tightly packed this performance tier is. The Athlon's closest competitor, the AMD Opteron 3280, matches its 1106 average exactly with a 0% delta. The Xeon's nearest rival, the AMD PRO A10-8850B, also matches its 1098 average with a 0% delta. So while the head-to-head results show a clear winner, both chips occupy a narrow performance band where the difference between winning and losing against other parts is often less than 1%.

FAQ

Q: Which processor is faster in multi-core workloads?

A: The Intel Xeon E5-1603 v3 wins all three multi-core tests. It scores 382 to 324 in Cinebench R15, 1595 to 1350 in R20, and 3798 to 3215 in R23. The deltas are -15.2%, -15.4%, and -15.4% respectively.

Q: Does the AMD Athlon X4 845 win any benchmarks?

A: No. The database records zero wins for the Athlon. The Xeon takes all five head-to-head benchmarks, including every single-core and multi-core test.

Q: How do the two processors compare in single-core performance?

A: The Xeon leads in both recorded single-core tests. In Cinebench R20 single-core, it scores 225 versus 190, a -15.6% delta. In R23 single-core, it scores 536 versus 453, a -15.5% delta. The Athlon's higher base clock does not produce a win here.

Q: Are these two processors in the same performance class?

A: Yes. Both are at the 31st percentile among all CPUs. Their average benchmark scores are nearly identical, with the Athlon at 1106 and the Xeon at 1098. The Xeon's advantage in the head-to-head tests is consistent, but both parts sit in a competitive tier where nearest rivals differ by only 0.1% to 0.2%.

Q: What are the closest competing processors for each?

A: The Athlon's nearest rival is the AMD Opteron 3280, which matches its 1106 average score with a 0% delta. The Xeon's nearest rival is the AMD PRO A10-8850B, which matches its 1098 average with a 0% delta. Other nearby rivals include the AMD PRO A12-8870 and AMD PRO A12-9800 for the Athlon, and the Intel Pentium 6805 and Intel Core i5-3450S for the Xeon.

Q: Is the performance difference consistent across all Cinebench versions?

A: Yes. The deltas range from -15.2% to -15.6% across R15, R20, and R23. The narrow spread of 0.4 percentage points indicates a stable performance gap that does not change with benchmark version or workload type.

Architecture Differences

The two chips come from fundamentally different design philosophies. The AMD Athlon X4 845 uses the Excavator architecture, codenamed Carrizo, built on a 28 nm process at GlobalFoundries. It integrates 3,100 million transistors on a 250 mm² die. The Intel Xeon E5-1603 v3 uses the Haswell architecture, codenamed Haswell-EP, built on a 22 nm process at Intel. It packs 2,600 million transistors onto a larger 356 mm² die.

The cache layouts are strikingly different. The Athlon has a 320 KB L1 cache and a 2 MB L2 cache, with no L3 cache at all. The Xeon has a 64 KB L1 cache per core and a 256 KB L2 cache per core, but it adds a 10 MB shared L3 cache. That L3 cache is a significant architectural advantage for the Xeon, as it provides a large pool of fast memory for frequently accessed data, which helps explain its consistent lead despite lower clocks.

Memory support also diverges sharply. The Athlon supports dual-channel DDR3 with a memory bandwidth of 34.1 GB/s and no ECC support. The Xeon supports quad-channel DDR4 with a memory bandwidth of 59.7 GB/s and full ECC support. The Xeon's memory subsystem offers nearly double the bandwidth, which is critical for server and workstation workloads that move large datasets.

The PCIe lane counts are another major differentiator. The Athlon provides 8 PCIe Gen 3 lanes from the CPU, while the Xeon provides 40 PCIe Gen 3 lanes. That fivefold difference in lane count makes the Xeon far more suitable for systems with multiple GPUs, high-end storage controllers, or other expansion-heavy configurations.

The Xeon also has no boost clock recorded in the database, meaning it runs at a fixed 2.80 GHz. The Athlon has a base clock of 3.50 GHz and a boost clock of 3.80 GHz. The Athlon is also multiplier-unlocked, allowing overclocking, while the Xeon is locked. The Xeon's TDP is 140 W, more than double the Athlon's 65 W, reflecting the power demands of its larger memory controller, L3 cache, and server-class feature set.

Specification Differences

The two processors differ on nearly every specification field. The Athlon has a base clock of 3.50 GHz and a boost clock of 3.80 GHz, while the Xeon has only a 2.80 GHz base clock with no boost clock recorded. The TDPs are 65 W for the Athlon and 140 W for the Xeon, a 75 W gap.

The sockets are incompatible: the Athlon uses AMD Socket FM2+, while the Xeon uses Intel Socket 2011-3. The process nodes differ (28 nm versus 22 nm), as do the foundries (GlobalFoundries versus Intel). Transistor counts are 3,100 million for the Athlon and 2,600 million for the Xeon, but the die sizes reverse that order, with the Athlon at 250 mm² and the Xeon at 356 mm².

Cache configurations are entirely different. The Athlon has 320 KB L1 and 2 MB L2, with no L3. The Xeon has per-core L1 and L2 (64 KB and 256 KB per core), plus a 10 MB shared L3. Memory support differs by generation and channel count: DDR3 dual-channel for the Athlon versus DDR4 quad-channel for the Xeon. Memory bandwidth is 34.1 GB/s versus 59.7 GB/s. ECC support is absent on the Athlon and present on the Xeon.

PCIe lanes differ dramatically, with the Athlon providing 8 Gen 3 lanes and the Xeon providing 40 Gen 3 lanes. The Athlon has an unlocked multiplier; the Xeon is locked. The market segments differ as well, with the Athlon classified as Desktop and the Xeon as Server/Workstation. Release dates are also different, with the Athlon launching in February 2016 and the Xeon in September 2014. The core count and thread count are identical at 4 cores and 4 threads, and both are end-of-life products.

Where Each One Wins

Based strictly on the benchmark data, the Intel Xeon E5-1603 v3 wins every recorded test. There are zero benchmark wins for the AMD Athlon X4 845 in the database. The Xeon's advantages are consistent across multi-core and single-core workloads, with deltas between -15.2% and -15.6% in all five tests.

The Xeon's strengths extend beyond raw Cinebench scores. Its 10 MB L3 cache, quad-channel DDR4 memory with 59.7 GB/s bandwidth, and 40 PCIe Gen 3 lanes make it the clear choice for memory-intensive and expansion-heavy workloads. The ECC memory support is a hard requirement for many server and workstation environments where data integrity is non-negotiable. The 140 W TDP, while high, is the price for that server-class feature set.

The Athlon's potential advantages are not visible in the benchmark results, but they exist in the specification sheet. Its 65 W TDP means it draws less than half the power of the Xeon. Its unlocked multiplier allows overclocking, which the locked Xeon cannot do. Its higher base and boost clocks (3.50 GHz and 3.80 GHz versus 2.80 GHz) could, in theory, benefit workloads that are sensitive to raw frequency, but the recorded Cinebench data shows the Xeon overcoming that frequency deficit in every test. The Athlon also uses the FM2+ socket, which pairs with lower-cost platforms, though the database does not record pricing.

For a practical builder, the choice depends on the platform requirements. If the workload demands ECC memory, quad-channel bandwidth, high PCIe lane counts, or a large L3 cache, the Xeon is the only option between these two. If the priority is low power consumption, overclocking headroom, or a legacy FM2+ platform, the Athlon has the specification-level advantages, but it cannot match the Xeon's performance in any recorded benchmark.

The Verdict

The benchmark data is unambiguous. The Intel Xeon E5-1603 v3 outperforms the AMD Athlon X4 845 in every single recorded test, with a consistent margin of approximately 15%. The Xeon wins all five head-to-head Cinebench tests, covering both multi-core and single-core workloads across R15, R20, and R23 versions. The Athlon records zero wins.

The Xeon's victory is not a narrow one. A 15% performance gap in both single-core and multi-core tests means the Xeon is simply the faster processor in all scenarios the database measures. Its lower base clock of 2.80 GHz is fully compensated by its Haswell architecture, 10 MB L3 cache, and superior memory subsystem. The Athlon's higher clocks and unlocked multiplier do not translate into any benchmark victory.

The decision for a builder should be driven by platform needs. Choose the Intel Xeon E5-1603 v3 if the workload requires ECC memory, quad-channel DDR4 bandwidth, 40 PCIe Gen 3 lanes, or server-class reliability. It is the faster chip in every measured test, and its feature set is designed for workstation and server environments. The 140 W TDP is a consideration, but it is the cost of that capability.

Choose the AMD Athlon X4 845 only if the platform constraints are absolute: a socket FM2+ board, a 65 W power envelope, or the need for an unlocked multiplier for overclocking. The database shows no performance scenario where the Athlon wins, but its lower power draw and overclocking flexibility are real specification-level advantages. For raw performance in Cinebench workloads, however, the Xeon is the definitive choice, and the data supports that verdict without qualification.