HP OMEN by 40L Gaming Desktop GT21-0xxx

Desktop, from 2022 4 hardware reports

4 full-size slots

Drives and power

Coming next

Checked from separate sources

Upgradable

Yes. 4 slots, up to 16 GB seen working.

It takes DDR4-3200 full-size sticks (DIMM).

Slots: 4 DIMM slots
Type: DDR4-3200 288-pin DIMM
Most seen working: 16 GB in two or more machines; one machine runs 32 GB
Firmware says: 64 GB maximum (often wrong, so we show what machines run)
How sure: 4 of 4 reports show this layout

See 4 GB DDR4-3200 DIMM on AmazonOpens an Amazon search for this exact spec.

Worked out from 4 hardware reports of this desktop. Sources and method. Updated 9 Nov 2026.

4 full-size slots

Illustration

Questions

Can I upgrade the RAM in the HP OMEN by 40L Gaming Desktop GT21-0xxx?

Yes. 4 slots, up to 16 GB seen working. It takes DDR4-3200 full-size sticks (DIMM).

What type of RAM does the HP OMEN by 40L Gaming Desktop GT21-0xxx use?

DDR4-3200 full-size sticks (DIMM, 288-pin).

How much RAM can the HP OMEN by 40L Gaming Desktop GT21-0xxx take?

Machines in the reports run up to 16 GB, and one runs 32 GB. The firmware reports a maximum of 64 GB, a figure that is often wrong.

Is this my desktop?

Check the model name on the front or the label of the case. It should read OMEN by 40L Gaming Desktop GT21-0xxx.

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