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SSD for Windows 11: DRAM, HMB and QLC beyond the capacity label

Verified 2 min read

Choose a Windows 11 system SSD by controller, DRAM/HMB, TLC/QLC, thermals and endurance, and verify TRIM/health instead of chasing sequential numbers.

Tested onPro (26H2) · Build 26300.9457 · x64
E1
Build
26300.9457
Edition
Pro (26H2)
Architecture
x64
Support
Documentation (E1)
Evidence
E1Official documentation
Verified
2026-10-28
Page type
Concept

The short answer

Section titled “The short answer”

For a Windows 11 system drive, the ranking is:

  1. NVMe, TLC, DRAM (or good HMB) — predictable.
  2. NVMe, TLC, HMB — usually fine.
  3. NVMe, QLC, DRAM/HMB — acceptable for a game/library drive, less ideal as the only system drive.
  4. No-name QLC, no DRAM/HMB — a lottery.

Sequential MB/s is the least useful number for Windows responsiveness. Random reads, write consistency and thermals matter more.

What the labels mean

Section titled “What the labels mean”
Term Meaning Why it matters
DRAM On-drive cache for mapping table Better sustained random writes
HMB Host Memory Buffer; uses system RAM Cheaper alternative to DRAM; quality varies
TLC 3 bits/cell Better endurance/write behaviour
QLC 4 bits/cell Cheaper, slower sustained writes
SLC cache Fast write buffer Once full, QLC can drop hard
TBW Endurance rating A rough warranty/endurance guide

System vs game drive

Section titled “System vs game drive”
  • System drive: OS, apps, browser cache, WSL VHDX. Prioritise random I/O, DRAM/HMB and consistent writes.
  • Game/library drive: capacity matters; QLC can be acceptable if you can tolerate slower installs.
  • Scratch/VM drive: sustained writes and thermals matter; a DRAM-less QLC drive is a poor choice.

Verify Windows is treating it correctly

Section titled “Verify Windows is treating it correctly”
Terminal window
Get-PhysicalDisk | Select-Object FriendlyName, MediaType, HealthStatus, OperationalStatus
Get-Volume
fsutil behavior query DisableDeleteNotify

DisableDeleteNotify = 0 means TRIM is enabled. Run Optimize Drives (dfrgui) and confirm the SSD is not being defragmented; Windows should send TRIM/retrim.

Thermals and firmware

Section titled “Thermals and firmware”
  • NVMe drives throttle when hot; a heatsink and airflow matter under sustained writes.
  • Update firmware only from the vendor, with a backup and stable power.
  • Check SMART/health; a drive reporting caution is a backup trigger, not a challenge.

Buying checklist

Section titled “Buying checklist”
  1. NVMe, not SATA, for the system drive.
  2. TLC preferred; QLC only with a good cache and a clear use case.
  3. DRAM or reputable HMB.
  4. 1TB minimum for Windows + apps + a few games.
  5. Heatsink/airflow for Gen4/Gen5.
  6. Warranty and TBW that match your workload.
  7. A second drive or external backup, not a second partition.
Section titled “Related hardware guides”

Sources