CPU-Z RAM Speed: DDR4 and DDR5 Memory Frequency Explained

What CPU-Z actually measures

In CPU-Z, open the Memory tab and find DRAM Frequency. This is the clock reported for the memory controller, not necessarily the advertised DDR transfer rate on the kit packaging. DDR means double data rate: transfers can occur on both clock edges.

Convert the value into a DDR rate

A reading near 1600 MHz corresponds to approximately DDR4-3200 (3200 MT/s); a reading near 2400 MHz corresponds to DDR5-4800 (4800 MT/s). Multiply the reported DRAM clock by about two. Do not confuse MHz (clock) with MT/s (data transfers per second).

Check whether the expected profile is active

Compare CPU-Z Memory values with the configured speed in BIOS/UEFI and the RAM kit specification. The SPD tab lists available profiles stored on the module; the Memory tab reports the current operating configuration. Seeing an XMP/EXPO profile in SPD does not prove it is enabled.

If the speed looks too low

Check each installed module, memory channel configuration and firmware settings. After changing an XMP/EXPO setting, boot normally and test stability before assuming it is safe. On laptops and OEM desktops, firmware may intentionally restrict memory profile changes.

Further reading and software

View CPU-Z features and download options · Windows hardware topics · How technical information is checked

Frequently asked questions

Does CPU-Z show DDR5 speed directly?

It displays DRAM clock; the effective DDR transfer rate is roughly twice that number.

Why does the SPD tab show a different frequency?

SPD describes stored specifications and optional profiles. The Memory tab shows current operating parameters.