Intel Xeon Generations Explained: What to Buy Used in 2026

Intel's support article 000059657, “Understanding Intel Xeon Processors: Numbers and Suffixes” (last reviewed June 16, 2026), warns that numbers and suffixes “are used to differentiate features within each processor family, not across different families”: a Gold 6132 and a Xeon W-2135 share a brand and nothing else. Inside the Scalable family the digits are a code, and a suffix can change meaning between generations:

Source: Intel support article 000059657 (June 16, 2026), condensed to the letters on used-market parts; examples from Intel ARK, September 4, 2026; the 2 TB figure from HPE's DL380 Gen10 QuickSpecs.

The second digit also fixes memory speed, PCIe generation and, as the tables below show, the hypervisor floor. Three families sit outside the scheme:

• Xeon E5-2600 v3 / v4 (2014–2016). E5-2600 is the two-socket line, E5-1600 the workstation line; v3 is Haswell (Q3 2014), v4 Broadwell (Q1 2016), per the ARK page of the E5-2699 v4. Both: LGA2011-3, four DDR4 channels, 40 PCIe 3.0 lanes, no AVX-512 (ARK lists AVX2 as the top extension).
• Xeon W (single-socket workstation). W-2100 (Skylake, Q3 2017) and W-2200 (Cascade Lake, Q4 2019) use LGA2066, four channels, 48 lanes; W-3200 (Q2 2019) uses LGA3647, six channels, 64 lanes; from 2023 the Sapphire Rapids parts are w3/w5/w7/w9-2400 and -3400.
• Xeon 6 (2024). The digits change meaning: 6900-series parts use the twelve-channel LGA7529 socket, 6700/6500-series the eight-channel LGA4710; a trailing P is a Performance-core part (6980P), E an Efficient-core part (6780E) — different chips, not bins.

Hardware cells come from each flagship's ARK page (opened September 4, 2026) or the OEM guide that names it; the last column is our live inventory the same day — “complete” means CPUs and memory included, stock in parentheses.

Sources: Intel ARK pages for the Platinum 8180, 8280, 8380, 8480+, 8592+, Xeon 6980P, 6780E, E5-2699 v3 and E5-2699 v4, opened September 4, 2026; OEM guides for the platform column, including Lenovo Press LP1049 and LP1971 (also in our spec-sheet library); PCSP live inventory, September 8, 2026. 16G is untracked stock, quoted to order.

Only the 1st→2nd and 4th→5th steps keep the socket; DDR5 arrives with the 4th gen. Intel ARK, September 4, 2026.

Only the 1st → 2nd and 4th → 5th steps keep the socket, and even then HPE's DL360 Gen11 QuickSpecs (document a00128934, October 30, 2025) state that a field upgrade from 4th- to 5th-gen processors is not supported: the 5th-gen firmware does not run on the system board shipped with 4th-gen parts, so a new server order is required. Cooper Lake (Platinum 8380H, Q2 2020) is printed as “3rd Gen” on its ARK page but is a 4/8-socket, six-channel, PCIe 3.0 part, not the Ice Lake-SP platform.

Core counts sell servers; per-core throughput and memory bandwidth run them. The yardstick is SPEC CPU2017 Integer Rate — published results on spec.org, index as served September 4, 2026, two-socket systems, base result; “per core” is base ÷ enabled cores, bandwidth the theoretical ARK figure (channels × MT/s × 8 bytes).

Sources: SPEC CPU2017 published results, spec.org index as served September 4, 2026; per core = base ÷ enabled cores (PCSP arithmetic); bandwidth theoretical from Intel ARK; the 4114 row uses ARK's DDR4-2400 ceiling for Silver.

Now our September 5 prices against PassMark CPU Mark, which is user-submitted, so we print the sample count. $/core = price ÷ cores; $ per 1,000 points = price ÷ (CPU Mark ÷ 1,000).

Sources: PCSP /refurbished-cpu/ live prices, September 8, 2026 (the Gold 5218 at $19.99 sold out on September 4 and is omitted, as is the single-unit E5-2697 v4); PassMark scores and sample counts read September 5, 2026; derived columns are PCSP arithmetic.

The $14.99 Gold 6132 costs $0.67 per 1,000 points; the $4.58 W-2235 is priced for clocks. PCSP prices September 8; PassMark scores September 5, 2026.

The Gold 6132 at $0.67 per 1,000 points is the cheapest compute on the shelf, while the two highest single-thread parts we stock, the W-2235 and Gold 6246, are the dearest per multi-thread point: the used market prices clocks, not cores. Above 2nd gen there is no used market yet: on September 4 a Gold 6338 was $1,199.95 at TechMikeNY, and the Platinum 8480+ and 8592+ appeared only at CloudNinjas, at $25,167.19 and $28,384.69 (asking prices), roughly twice Intel's recommended $11,995 and $12,992 on ARK.

The R line is the value line, not the Skylake Gold. A Gold 6248R (24 cores, 205 W, Q1 2020, per ARK) was $342.04 at SaveMyServer and $499.95 at TechMikeNY on September 4 (asking prices) against the $14.99 Gold 6132; SPEC per core 7.6 against 5.9 and PassMark 36,067 (10 samples) against 22,509 explain the gap, and ServeTheHome (March 26, 2020) measured the refresh “20-30% higher” than its predecessor. It drops into the same LGA3647 socket, but check the vendor's processor list for your board revision.

Power: Idle and Peak by Platform Generation

A TDP is a cooling specification, not a power bill. SPECpower_ssj2008 publishes whole-server watts at active idle and at 100% load for tuned submissions (minimal drives, power-saving BIOS), so idle figures are floors; index as served September 4, 2026, one two-socket result per generation.

Source: SPECpower_ssj2008 published results (spec.org), index as served September 4, 2026; where a platform has two runs the earlier is shown; the E5 v3/v4 rows carry only the month in the index.

Idle rose from 44.9 W on E5 v4 to 241 W on Xeon 6; full load more than quadrupled. SPECpower_ssj2008, September 4, 2026.

The old platforms idle at 45–55 W, Ice Lake at 131 W, the DDR5 generations at 163–241 W. Efficiency roughly doubled (ssj_ops/W from about 11,000 in 2016 to 20,500–22,800 in 2025–2026) while work per box moved far more: the R770AP's 31.4 million ssj_ops at 100% load is 9.4 times the R730's 3.3 million, for 4.4 times the peak watts. At our home-lab article's $1.61 per watt per year, 45 W of idle costs about $72 a year, 241 W about $388; the rack that is 15% busy belongs to the old generation.

Here the second digit turns into a date; every cell is vendor wording from the documents in the caption. Proxmox VE is absent because it publishes no CPU-generation floor — “64-bit x86 (Intel 64 or AMD64)” with “Intel VT or AMD-V” — so every row runs it.

Sources: Broadcom KB 318697 (VCF 9.x, July 9, 2026) and KB 428874 (updated July 4, 2026); VMware vSphere 8.0 release notes (October 11, 2022); Proxmox VE System Requirements (wiki, November 28, 2024); Dell PowerEdge / Windows Server OS support matrix (PDF, December 17, 2025); Microsoft Windows 11 supported Intel processors (October 16, 2025) and the 25H2 / 24H2 pages. All opened September 4–5, 2026.

VMware, in Broadcom's definitions. KB 318697: “Deprecated mode means it is still Supported by VMware” — the installer prints “CPU_SUPPORT_WARNING: The CPUs in this host may not be supported in future VCF releases” — while “In the Phase 2 Discontinued phase, the ESX/VCF installer will block or prevent the installation.” An upgrade showing the warning may proceed (KB 413002). For ESXi 8.0 the only live statement is the release notes' rule that 8.0 “no longer supports CPUs which have been marked as End of Support or End of Life from hardware vendors” (the old per-family KB 82794 now redirects into the 9.x article). The alternative is leaving VMware: our VMware-to-Proxmox guide covers the move, and Proxmox VE 9.2 (released May 21, 2026) installs on anything with VT-x.

Windows Server: Microsoft's floor is trivial; the OEM matrix is the gate. Microsoft's hardware requirements page (updated August 10, 2026) adds only SSE4.2 and POPCNT for Server 2025, present on every processor in the ladder; what stops an R640 is Dell's missing column. HPE's certification matrix, checked August 28, 2026 for our Windows Server 2012 exit-plan article, lists the DL360 and DL380 Gen10 through Server 2025 — the same silicon Dell stops at 2022.

Windows 11 for the workstation towers. By CPU, Microsoft's general list clears the W-2100/W-2200 towers (Precision 5820, HP Z4 G4, ThinkStation P520) and the two-socket 7820/7920, Z6/Z8 G4 and P720/P920; the per-version 24H2 and 25H2 pages omit the W-2100 to W-3200 series. No Xeon E5 or E3 v5/v6 is on any list, so the T5810/T7810/T7910, Z440/Z640/Z840 and P510/P710/P910 towers are out by CPU. An earlier compatibility list of ours used the narrower per-version list for W-2100/W-2200 machines and is being corrected; TPM 2.0 is required either way.

The forum premise that E5 v4 or Skylake-SP is “end of life for security updates” we could not verify. Intel has published no end-of-servicing statement for any Xeon Scalable generation or for E5 v3/v4, and its “End of Servicing Update for Skylake Products” (July 27, 2022) says that “this ESU does not apply to Skylake server products (1st Generation Intel Xeon Scalable Processors)”. The release record is easy to misread: the microcode-20260811 release updates ICX-SP (3rd gen), SPR-SP (4th), EMR-SP (5th) and GNR (Xeon 6 P-core), and neither it nor the May 12, 2026 release touches family 06-55 (Skylake-SP, Cascade Lake), 06-4F (Broadwell-EP) or 06-3F (Haswell-EP). Intel's affected-processors table, read September 5, 2026, says why: on every issue disclosed in 2025–2026 those three families read “Not Affected”.

The older issues decide performance, and there the same table reads the other way. Haswell-EP, Broadwell-EP and Skylake Server take Spectre v2, L1TF, MDS and the 2022 MMIO class as “MCU + Software” — microcode plus OS mitigations — where Ice Lake-SP is “Not Affected” by L1TF and MDS, Sapphire and Emerald Rapids also by the MMIO class, and both fix Spectre v2 in hardware; Haswell-EP and Broadwell-EP additionally show “No planned mitigation” for Snoop-assisted L1D Sampling, LVI and RAPL. Downfall is the one with a number attached. INTEL-SA-00828 (August 8, 2023; CVE-2022-40982) covers “certain vector execution units”, and Intel's Gather Data Sampling paper says the microcode mitigation is on by default and that “specific workloads may show performance impacts of up to 50%” — gather-heavy HPC and graphics code. It lands on Skylake-SP (stepping 4), Cooper Lake and Ice Lake-SP, not on E5 v3/v4 or the 4th and 5th gen. We print no percentage for Spectre, L1TF and MDS: no Intel page with a figure was opened for this article.

Intel retires a family with a Product Change Notification fixing last-order and last-ship dates; its discontinuance policy page says the schedule “varies by product family”. The dated record:

Sources as linked; PCN PDFs opened September 4, 2026. “Press-reported” marks milestones we could not confirm against the PCN itself. No PCN was found for 1st-gen Scalable (other than the 2019 notice on -F Omni-Path SKUs) or for Ice Lake-SP.

Intel's calendar is about new-chip sales, not your server: used supply comes from decommissioned fleets, and our 157 Gold 6132s show Skylake-SP arriving in volume six years after Cascade Lake replaced it. Above the ladder, Intel's June 1, 2026 blog introduced Xeon 6+ (Clearwater Forest) and ServeTheHome reports Diamond Rapids as a 2027 part: no new wave pushes 3rd/4th-gen parts into the used market this year.

The generation sets memory type and speed, and memory, not the processor, moves the invoice. Our DDR4 RDIMM shelf on September 8, 2026, priced almost flat per gigabyte within each speed:

Sources: PCSP /components/ram-memory/ live prices, September 8, 2026, single ECC RDIMMs; kits are lots of 8 or 16 GB modules; $/GB = price ÷ capacity — on this date the kits priced at the same $/GB as single modules. DDR5 figures are other dealers' asking prices and a price tracker's listings the same day.

For one server: 128 GB in a 1st-gen R640 at DDR4-2666 is an 8× 16 GB kit at $863.92 ($6.75 per GB); the same 128 GB at DDR4-3200 for a 3rd-gen R750 is $1,503.84 ($11.75 per GB); for a 4th-gen R760, four 32 GB DDR5 RDIMMs at the cheapest asking price we found come to $3,999.96. Per 32 GB module, DDR5 at $999.99–$1,268.99 is 4.6 to 5.9 times our $215.99 DDR4-2666 part — the ratio that keeps LGA3647 and LGA4189 rational in 2026 for everything not bandwidth-bound. TrendForce's July 9, 2026 forecast (an analyst estimate) says “a server DRAM shortage is already anticipated for 2027”; refurbished DDR4 is already built, so its price rises while its supply does not vanish — our refurbished DDR4 memory article works through buy-now-or-wait.

The ladder, the compatibility table and the memory bill collapse into one decision table; every example is a live listing on September 4, 2026.

Source: PCSP live inventory, September 8, 2026 (units are the listing's stock pool shared by several configurations; 16G quoted to order).

Home labs have their own row in our home-lab article, from a $104.99 R730 barebones; our SR630 vs R640 comparison and the R750 review go deeper on two rows above; the used-server buying checklist is the same for every generation.

We sell up to the 2nd gen at volume, the 3rd barely at all; here the cheap socket is wrong:

• VMware Cloud Foundation 9. E5 v4 will not install, Skylake-SP ends at 9.1.x, Cascade Lake is warned now, discontinued next major release: buy 3rd gen or newer, or budget the migration.
• Windows Server 2025 on Dell 13G/14G. Dell lists neither; the routes are HPE Gen10 (carried to 2025), Dell 15G, or Server 2022 on 14G, patched to October 2031 — priced in our WS2012 exit-plan article.
• AVX-512 or AMX software. No E5 v3/v4 has AVX-512, AMX starts at the 4th gen, 1st-gen Silver and Gold 5 have one FMA unit, and Downfall's mitigation costs Skylake-SP and Ice Lake-SP Intel's own “up to 50%” on gather-heavy code.
• Bandwidth-bound work. 128–141 GB/s per socket on LGA3647 against 307–358 on LGA4677 and 614 on Xeon 6900P; in-memory databases feel it first.
• Power- or space-capped racks. New generations are about twice as efficient per unit of work and one R770AP does the 100%-load work of roughly nine E5 v4 R730s: consolidation wins even at DDR5 prices.
• OEM lifecycle rules. Dell publishes no end-of-support-life schedule but already brackets 13G, R440, R540, R740xd and T640 as “discontinued platforms”; Lenovo's SR630/SR650 guides read “withdrawn product”. Our one-year warranty (extendable to five) is not a manufacturer SLA.
• DDR5 expansion. We hold none; a 4th/5th-gen host from us ships with its memory and grows at new-market prices — price 1 TB per host new first.
• When new is right. Mercury Research's Q2 2026 estimate (The Register, August 21, 2026) puts AMD at 34.5% of server CPU units and 46.4% of revenue; our nine EPYC configurations against 184 complete 1st-gen Intel machines show where used supply sits, not what to run in 2030.

Our own gaps: one complete 3rd-gen machine (R750, 4 units); 4th/5th gen to order only, a lead time, not a shelf; no loose CPU newer than the Gold 6246 (3 units) since the Gold 5218 sold on September 4; the DL360 Gen10 Plus, our only 3rd-gen HPE, sold out.

What is the maximum number of threads on a single Xeon E5 CPU?

44 threads: the E5-2699 v4 is 22 cores / 44 threads (Intel ARK); the E5 v3 ceiling is the E5-2699 v3 at 18 / 36, $20.78 on our shelf on September 8, 2026. The bigger E7-8890 v4 (24 / 48) needs a 4- or 8-socket board. Later sockets reach 56 (Platinum 8180/8280), 112 (8480+) or 256 threads (Xeon 6980P).

Is the Xeon Silver 4114 still good in 2026?

For file servers, Proxmox or Hyper-V hosts, yes; for VMware VCF 9, no. It is a 1st-gen part: 10 cores, 85 W, DDR4-2400, one AVX-512 FMA unit, PassMark 13,167. Complete hosts on it start at $867.29 (R640, 64 GB) as of September 8, 2026. Dell qualifies the R640 to Windows Server 2022; Broadcom supports Skylake-SP only through VCF 9.1.x.

Xeon Gold 6132 vs Gold 6154: which one to buy?

Both are 1st-gen Skylake-SP, LGA3647: 6132 = 14 cores, 2.60 GHz, 140 W; 6154 = 18 cores, 3.00 GHz, 200 W; PassMark 22,509 versus 27,672. September 8, 2026: we list the 6132 at $14.99 (157 units), the 6154 at $69.99 (65), so $0.67 versus $2.53 per 1,000 points. Buy the 6132 unless a per-core licence justifies the clock.

What generation is the Xeon W-2235, and what does it fit?

Cascade Lake-W, the Xeon W-2200 series (Q4 2019): 6 cores, 130 W, LGA2066, four DDR4-2933 channels, 48 PCIe lanes, AVX-512. A single-socket part for the Precision 5820, HP Z4 G4 and ThinkStation P520; its 2,603 PassMark single-thread score is the highest we stock, and Microsoft's general Windows 11 list includes W-2200. $64.99, 159 units, September 8, 2026.

Xeon E5-2687W v4 vs a Xeon Gold: is the Gold faster?

Per core, yes. The E5-2687W v4 (Broadwell, LGA2011-3) is 12 cores, 160 W, no AVX-512; a 2nd-gen Gold 6246 (LGA3647) scores 7.8 per core on SPEC CPU2017 against 5.3 for the E5-2680 v4, the nearest Broadwell-EP with a published two-socket result (the 2687W v4 has none). The 6246 needs a 14G, Gen10 or P720/P920-class board, while the 2687W v4 drops into a Z640, T7810 or P710. The 6246 is $99.99 on our shelf, September 8, 2026.

Can a 1st-gen Skylake-SP server run ESXi 8 or VCF 9?

Yes, for now. ESXi 8.0 installs with a CPU_SUPPORT_WARNING; Broadcom's only stated 8.0 rule concerns CPUs marked end of life by their hardware vendor. For VCF 9, KB 428874 (July 4, 2026) says Skylake-SP is “supported in Deprecated Mode for VCF 9.1.x” and “will not be extended” beyond it; KB 318697 lists it as discontinued (installer blocked) from 9.2.

Does a Dell PowerEdge R640 support Windows Server 2025?

Not per Dell. Microsoft's floor (SSE4.2, POPCNT) is met by every Xeon Scalable, but Dell's OS matrix (December 2025) qualifies the R640 and R740 for Server 2022, 2019 and 2016 only; Server 2025 begins at 15G (R650/R750). HPE takes the same silicon, DL360/DL380 Gen10, to Server 2025; on an R640 the path is Server 2022, supported to October 2031.

Does Intel still patch Xeon E5 v4 and 1st-gen Scalable processors?

Intel has published no end-of-servicing statement for either; its 2022 Skylake end-of-servicing update excludes 1st-gen Xeon Scalable. The 2026 microcode releases (May 12, August 11) update 3rd-gen and newer only, and Intel's affected-processors table marks Haswell-EP, Broadwell-EP and Skylake Server “Not Affected” by every 2025–2026 issue. Older mitigations (Spectre, L1TF, MDS, MMIO) are in BIOS and OS microcode.