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Why HWiNFO64 Shows 2000 MHz for XMP DDR4-4000 RAM Explained

HWiNFO64 shows the DRAM base clock (2000 MHz) when XMP PC-4000 is active; double that value to get DDR4-4000 (4000 MT/s). See DRAM Frequency in HWiNFO64 sensors.

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Why does HWiNFO64 report my RAM frequency as 2000 MHz even though I enabled the XMP PC-4000 profile in BIOS? Is the 2000 MHz value the actual DRAM base clock, the DDR/effective rate (4000 MT/s), or half the advertised frequency? Where in HWiNFO64 (or in the displayed window/screenshot) can I find the multiplier or the field that shows the effective memory speed?

HWiNFO64 reports 2000 MHz because it’s showing the DRAM base clock; with an XMP PC‑4000 profile the effective DDR rate is 4000 MT/s (DDR4‑4000), so the 2000 MHz value is the actual base clock and therefore half the advertised transfer rate. HWiNFO64 doesn’t display a separate “multiplier” for DDR doubling — look for fields named “DRAM Frequency”, “Memory Clock” or “Current Memory Frequency” in the Memory section or Sensors window and double that number to get the effective MT/s.

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HWiNFO64 and XMP: why it shows 2000 MHz for DDR4‑4000

Seeing 2000 MHz in HWiNFO64 right after enabling an XMP PC‑4000 profile is expected behavior, not a bug. Tools like HWiNFO64 and CPU‑Z report the raw DRAM clock (the actual oscillator frequency), while manufacturers advertise the effective transfer rate (MT/s) that results from DDR’s double‑data‑rate operation. Community threads documenting this behavior explain the same: HWiNFO shows the base DRAM clock and you must multiply by two to get MT/s (so 2000 MHz → 4000 MT/s) — see several HWiNFO forum examples that call this out explicitly https://www.hwinfo.com/forum/threads/hwinfo-shows-half-ram-speed.6042/ and https://www.hwinfo.com/forum/threads/why-are-memory-module-maximum-clock-and-current-system-memory-clock-different.6537/.

Put simply: the 2000 MHz number is the actual DRAM base clock; the advertised “4000” (PC‑4000 / DDR4‑4000) is the effective transfer rate in MT/s.

Where to find DRAM Frequency / effective speed in HWiNFO64

Open HWiNFO64 and run either the full summary or the Sensors‑only mode (Sensors-only is easiest for quick checks). Look in two places:

  • Main summary (hardware tree): expand the Memory or Motherboard → Memory node. The right‑hand pane will list a field called DRAM Frequency or Memory Clock (this is the base clock in MHz).
  • Sensors window: in the sensors list you’ll often see Current Memory Frequency, Memory Clock, or similar per‑channel entries — again, these are base MHz values.

Example interpretation: if HWiNFO shows “DRAM Frequency: 2000.0 MHz”, double that to get the effective data rate: 2000 × 2 = 4000 MT/s (DDR4‑4000). The HWiNFO forum threads note these exact field names and where to look in the UI https://www.hwinfo.com/forum/threads/memory-information-contradiction-why.6324/ and https://www.hwinfo.com/forum/threads/current-memory-frequency.8075/.

One important detail: HWiNFO doesn’t provide a separate “x2 multiplier” field because the doubling is inherent to DDR technology — the app reports the hardware clock and leaves the MT/s conversion implicit.

DDR doubling explained: base clock vs MT/s

Why does DDR look like “half speed”? Because DDR (Double Data Rate) transfers data on both the rising and falling edges of the clock. That means the transfer rate (MT/s) is twice the physical clock frequency:

Effective MT/s=2×DRAM base (MHz)\text{Effective MT/s} = 2 \times \text{DRAM base (MHz)}

So:

  • DRAM base = 2000 MHz → Effective = 4000 MT/s (advertised as DDR4‑4000 / PC‑4000).
  • DRAM base = 1066 MHz → Effective = 2133 MT/s (this is why default JEDEC 2133 shows ~1066 in tools).

Multiple user reports and hardware discussions cover this exact point; they show the same behavior in HWiNFO, CPU‑Z and other utilities — the tool reports the physical clock and you multiply by two to read the advertised DDR rate https://forums.tomshardware.com/threads/ram-in-bios-shows-4100-or-4000-more-stable-mhz-however-cpu-z-shows-2000mhz.3349814/ and https://www.hwinfo.com/forum/threads/ram-speed-report-hwinfo.10445/.

So when you see “half” the advertised number, it’s not that the RAM is underperforming — it’s the units and convention.

Verify XMP (PC‑4000) is applied and troubleshoot if you don’t see expected speed

If you enabled XMP in BIOS but still see a lower effective rate (or HWiNFO shows a smaller base clock), run this quick verification and troubleshooting flow:

  1. Reboot into UEFI/BIOS and confirm XMP/DOCP/EXPO is enabled and the profile selected is the PC‑4000/DDR4‑4000 profile. The BIOS will usually show the target frequency and timings. If BIOS shows a JEDEC default (e.g., 2133 MT/s), XMP didn’t stick. HWiNFO forum posts walk through this behavior https://www.hwinfo.com/forum/threads/memory-information-contradiction-why.6324/.
  2. Back in Windows, open HWiNFO64 and check DRAM Frequency or Current Memory Frequency (Sensors). If you see 2000 MHz there, that indicates the XMP profile is active (2000×2 = 4000 MT/s). Community threads confirm that HWiNFO shows the base clock even with XMP active https://www.hwinfo.com/forum/threads/hwinfo-shows-half-ram-speed.6042/.
  3. Use CPU‑Z (Memory tab) to cross‑check: CPU‑Z also shows the DRAM Frequency (base) — here too you’ll see ~2000 MHz for DDR4‑4000. See real‑world reports of this behavior on Tom’s Hardware and Reddit https://forums.tomshardware.com/threads/ram-in-bios-shows-4100-or-4000-more-stable-mhz-however-cpu-z-shows-2000mhz.3349814/ and https://www.reddit.com/r/buildapc/comments/n2op36/ddr44000_ram_showing_2000mhz_in_cpuid/.
  4. If HWiNFO shows a lower base (for example ~1066 MHz instead of 2000), XMP hasn’t applied or the system reverted to JEDEC defaults. Causes include instability (XMP is an overclock), incompatible DIMMs, using non‑matched modules instead of a factory kit, or motherboard/CPU memory controller limits. The HWiNFO community often points out that XMP = overclocking and instability may cause automatic fallback https://www.hwinfo.com/forum/threads/current-memory-frequency.8075/.
  5. Fixes: enable the correct XMP profile (Profile 1 typically), ensure both DIMMs are in the recommended slots, check the motherboard QVL and BIOS version, update BIOS if needed, and consider manually entering XMP timings/voltage if auto‑apply fails.

If you still have doubts after these checks, post a screenshot of HWiNFO’s Memory summary (or Sensors window) — it usually makes diagnosis straightforward because the DRAM Frequency field is explicit.

Quick checklist and commands to confirm memory speed

  • Expected readouts (what you should see):

  • BIOS: XMP/DOCP enabled; target = DDR4‑4000 or 4000 MT/s shown in BIOS UI.

  • HWiNFO64 (Main/Sensors): DRAM Frequency ≈ 2000.0 MHz → double it = 4000 MT/s.

  • CPU‑Z (Memory tab): DRAM Frequency ≈ 2000 MHz → double it.

  • Fast checklist:

  • Reboot → BIOS: XMP = enabled? profile = PC‑4000?

  • Windows → HWiNFO64: open Sensors → find “DRAM Frequency” or “Current Memory Frequency”.

  • Cross‑check with CPU‑Z SPD tab for the XMP profile and timings.

  • Useful commands (Windows):

  • PowerShell: Get memory module info:
    Get-CimInstance -ClassName Win32_PhysicalMemory | Format-Table BankLabel, Speed, Manufacturer
    (Speed may show the module’s SPD/programmed speed but HWiNFO/CPU‑Z are still the most reliable for live clock.)

  • Useful command (Linux):

  • sudo dmidecode --type 17 (look for Speed / Configured Clock Speed)

If HWiNFO shows the expected base MHz and BIOS shows XMP enabled, you’re running at the advertised DDR4‑4000 rate — just remember the tool reports the base clock.

Sources

Conclusion

HWiNFO64 is showing the DRAM base clock (2000 MHz) rather than the doubled DDR transfer rate; double the DRAM Frequency value to get the effective MT/s (2000 → 4000 MT/s for a PC‑4000 / DDR4‑4000 XMP profile). To confirm XMP is actually applied, check BIOS for the active XMP/DOCP profile, verify DRAM Frequency or Current Memory Frequency in HWiNFO64’s main or sensors view, and cross‑check with CPU‑Z’s Memory/SPD tabs. If values don’t match expectations, the usual culprits are XMP not applied or stability/compatibility fallbacks — check slots, kit pairing, voltage/timings and update BIOS as needed.

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Why HWiNFO64 Shows 2000 MHz for XMP DDR4-4000 RAM Explained