Intel Xeon E3-1240 v5 vs Intel Xeon E3-1585 v5 Comparison

Head-to-Head Benchmarks

The recorded data shows a clean sweep for the Intel Xeon E3-1585 v5 across all six Cinebench comparisons. The margin is consistent, though not dramatic. In Cinebench R15 multi-core, the E3-1585 v5 scores 720 against 707 for the E3-1240 v5, a 1.8% advantage. The single-core R15 result is similar: 101 versus 99, a 2% lead. These are small but repeatable edges.

Moving to Cinebench R20, the pattern holds. The E3-1585 v5 posts 3001 multi-core versus 2948, again a 1.8% delta. Single-core R20 shows 423 against 416, a 1.7% gap. The R23 results mirror this exactly in percentage terms. Multi-core is 7146 versus 7020 (1.8%), and single-core is 1008 versus 991 (1.7%). The win count is 6 for the E3-1585 v5, 0 for the E3-1240 v5.

What is interesting is that the relative gap does not widen in multi-threaded workloads. Both chips have the same core and thread count, and both boost to the same 3.90 GHz. The difference is likely due to other architectural factors, not raw parallelism. The single-core deltas are actually the largest in percentage terms, which suggests the E3-1585 v5 has a slight per-thread efficiency advantage rather than a scaling advantage.

The overall average benchmark scores place these two close in the broader database. The E3-1585 v5 has an average score of 2067, while the E3-1240 v5 averages 2030. That is a 1.8% difference in the aggregate, consistent with the per-test deltas. Percentile rankings reflect this near parity: the E3-1585 v5 sits at the 46th percentile of all CPUs, while the E3-1240 v5 is at the 45th. Neither chip is a standout in the wider market, but within this pairing, the E3-1585 v5 is clearly the faster part.

Architecture Differences

Both processors are built on Intel's 14 nm Skylake architecture, but they come from different variants. The E3-1585 v5 uses the Skylake-H die, while the E3-1240 v5 uses Skylake-DT. This is reflected in the transistor counts and die sizes. The E3-1585 v5 has 2,300 million transistors on a 171 mm² die. The E3-1240 v5 has 1,750 million transistors on a 122 mm² die. The Skylake-H die is significantly larger, which makes sense given the additional integrated graphics hardware.

The most obvious functional difference is the integrated GPU. The E3-1585 v5 includes Iris Pro Graphics P580, while the E3-1240 v5 has no integrated graphics at all. This is a major differentiator for systems that need display output or GPU-accelerated compute without a discrete card. The Iris Pro P580 is a capable solution for basic graphics tasks, though the benchmark data here only covers CPU performance.

The socket situation also differs. The E3-1585 v5 uses Intel BGA 1440, which means it is soldered to the motherboard. The E3-1240 v5 uses Intel Socket 1151, a standard LGA socket that allows for replacement or upgrade. This has practical implications for system longevity and serviceability, though the performance data is unaffected.

Cache layouts are identical: 64 KB L1 per core, 256 KB L2 per core, and 8 MB shared L3. Memory support is the same as well, with DDR3 and DDR4, dual-channel bus, and 34.1 GB/s bandwidth. Both support ECC memory, which is expected for the Xeon E3 line. PCIe is also identical: Gen 3 with 16 CPU lanes.

The TDP figures differ notably. The E3-1585 v5 is rated at 65 W, while the E3-1240 v5 is rated at 80 W. This is counterintuitive given that the E3-1585 v5 is the faster chip in benchmarks. The lower TDP likely comes from the Skylake-H design being optimized for mobile-ish platforms, despite being marketed as server/workstation. The E3-1240 v5, with its desktop-derived Skylake-DT die, draws more power while delivering slightly less performance.

Release dates also differ. The E3-1240 v5 launched on 2015-10-18, while the E3-1585 v5 came later on 2016-05-30. Both are now end-of-life products. The part numbers are SR2LD for the E3-1240 v5 and SR2RB for the E3-1585 v5.

FAQ

Q: Which processor has the higher multi-core performance?

A: The Intel Xeon E3-1585 v5 wins in every multi-core test recorded. In Cinebench R15, it scores 720 versus 707 for the E3-1240 v5. In R20, it scores 3001 versus 2948. In R23, it scores 7146 versus 7020. The margin is consistently 1.8%.

Q: How do the base and boost clocks compare?

A: They are identical. Both CPUs have a base clock of 3.50 GHz and a boost clock of 3.90 GHz. Despite this, the E3-1585 v5 outperforms the E3-1240 v5 in all recorded benchmarks.

Q: Do these processors support ECC memory?

A: Yes, both support ECC memory. They also share the same memory support for DDR3 and DDR4, with a dual-channel bus and 34.1 GB/s bandwidth.

Q: Is there any difference in integrated graphics?

A: Yes, this is a major difference. The E3-1585 v5 includes Iris Pro Graphics P580, while the E3-1240 v5 has no integrated graphics. This makes the E3-1585 v5 suitable for systems without a discrete GPU.

Q: What are the socket requirements for each?

A: The E3-1585 v5 uses Intel BGA 1440, a soldered BGA socket. The E3-1240 v5 uses Intel Socket 1151, a standard LGA socket. This affects upgradeability and motherboard compatibility.

Q: Which chip has a higher average benchmark score?

A: The E3-1585 v5 has an average benchmark score of 2067, while the E3-1240 v5 averages 2030. The E3-1585 v5 also ranks at the 46th percentile of all CPUs, one point above the E3-1240 v5's 45th percentile.

Specification Differences

The two CPUs diverge in several specification fields, while sharing many others. Here are the exact differences from the database:

• Transistors: The E3-1585 v5 has 2,300 million transistors. The E3-1240 v5 has 1,750 million.
• Die Size: The E3-1585 v5 measures 171 mm². The E3-1240 v5 measures 122 mm².
• Socket: The E3-1585 v5 uses Intel BGA 1440. The E3-1240 v5 uses Intel Socket 1151.
• TDP: The E3-1585 v5 is rated at 65 W. The E3-1240 v5 is rated at 80 W.
• Integrated Graphics: The E3-1585 v5 includes Iris Pro Graphics P580. The E3-1240 v5 has none.
• Codename: The E3-1585 v5 is Skylake-H. The E3-1240 v5 is Skylake-DT.
• Release Date: The E3-1585 v5 launched on 2016-05-30. The E3-1240 v5 launched on 2015-10-18.
• Launch MSRP: The E3-1585 v5 had a launch MSRP of $556. The E3-1240 v5 had a launch MSRP of $282.
• Part Number: The E3-1585 v5 is SR2RB. The E3-1240 v5 is SR2LD.

All other recorded specifications are identical: 4 cores, 8 threads, 3.50 GHz base, 3.90 GHz boost, 14 nm process, same cache hierarchy, same memory support, same PCIe configuration, and both are end-of-life with locked multipliers.

Where Each One Wins

The Intel Xeon E3-1585 v5 wins in every CPU benchmark category recorded. It is faster in single-core and multi-core tests across Cinebench R15, R20, and R23. The margins are 1.7% to 2%, which is small but consistent. For any workload that depends on raw CPU throughput, the data points to the E3-1585 v5.

The E3-1240 v5 has no benchmark wins in this comparison, but it still has clear advantages in other dimensions. Its socket is more flexible. Intel Socket 1151 is a standard LGA platform, meaning the CPU can be replaced or upgraded. The E3-1585 v5 is soldered via BGA 1440, which makes it a permanent part of the motherboard.

Power consumption is another area where the E3-1240 v5 could be preferred in a different sense. It has a higher TDP of 80 W versus 65 W, which is odd given its lower performance. However, this higher TDP might indicate a different thermal design point that some systems could accommodate more easily, depending on cooling infrastructure. The database does not record thermal performance, so this remains speculative.

The E3-1585 v5 is the clear choice for systems that need integrated graphics. Its Iris Pro Graphics P580 provides display output and GPU functionality without a discrete card. The E3-1240 v5 offers no such capability, requiring a separate GPU for any visual output.

For cost-sensitive system designs, the E3-1240 v5 has a launch MSRP of $282, which is lower than the E3-1585 v5's $556. This price difference is substantial, but the database does not track current market pricing.

The Verdict

The benchmark data is unambiguous. The Intel Xeon E3-1585 v5 outperforms the Intel Xeon E3-1240 v5 in every recorded test, with margins ranging from 1.7% to 2%. Its average benchmark score of 2067 is higher than the E3-1240 v5's 2030, and its percentile ranking is one point higher. For pure CPU performance, the E3-1585 v5 is the better part.

However, the E3-1240 v5 still has a role for specific use cases. Its standard Socket 1151 means it fits into conventional LGA motherboards, offering easier serviceability and upgrade paths. Its lower launch MSRP of $282 versus $556 makes it a more economical choice for systems where the integrated GPU of the E3-1585 v5 is not needed. The lack of integrated graphics is a non-issue in servers or workstations that use discrete GPUs.

The TDP difference is worth noting. The E3-1585 v5 draws 65 W while delivering more performance, while the E3-1240 v5 draws 80 W for slightly less. This suggests the E3-1585 v5 is more power-efficient in the recorded workloads, though the database does not include efficiency benchmarks.

The verdict depends on system requirements. If the workload benefits from integrated graphics, or if power efficiency is a priority, the E3-1585 v5 is the clear pick. If the system uses a discrete GPU and relies on a standard LGA socket for flexibility, or if launch price is a constraint, the E3-1240 v5 remains a viable option. The performance gap is real but modest, so the deciding factors are likely to be platform compatibility and feature requirements rather than raw speed.