I've seen the same problem on two different PCs with clean Windows 11 installations. Every so often, the system freezes for a few seconds while Task Manager reports the system SATA SSD at 100% active time. The first PC used a newer 1 TB SSD, and replacing it with an M.2 drive seemed to solve the issue. Now my daughter's PC has the same behavior with a reused 512 GB SanDisk SATA SSD.
The second installation was performed with Microsoft's Media Creation Tool, and the only installed software is Firefox, NVIDIA drivers, K-Lite Codec Pack, Minecraft, and Steam. Steam is installed on another drive. CrystalDiskInfo reports the SSD health as Good at 100%, the drivers are current, and the system has an Intel i7, Gigabyte Z890 motherboard, and 32 GB of RAM.
The odd part is that read and write throughput usually stays near 0 MB/s while active time is at 100%. CPU usage remains around 1–2%, and the drive becomes responsive again after a few seconds. Could this be a failing or slow DRAM-less SATA SSD, a controller or cable issue, Windows background activity, or a power-management setting such as AHCI or PCIe Link State Power Management?
2 Answers
A SATA SSD can report 100% active time even when the actual transfer rate is almost zero. That usually means the drive is busy handling a request or is experiencing high response latency, not that it is transferring data at its maximum speed. Older or DRAM-less SATA drives can pause badly during random reads and writes, especially under Windows background activity, indexing, Defender scans, updates, and virtual-memory use.
Before changing BIOS settings, check Resource Monitor rather than only Task Manager. Look at the Disk and Disk Activity sections during the freeze to see which file or process is generating the request and whether the response time spikes. Also check Event Viewer for disk, storahci, controller, or reset errors. If the same SSD behaves normally in another system but this one still pauses, investigate the SATA cable, motherboard SATA port, chipset/storage drivers, and SSD firmware. Replacing the old system drive with a decent SATA or NVMe SSD is also a reasonable practical fix if the pauses continue.
CrystalDiskInfo showing Good only confirms that the drive’s reported health counters have not crossed their failure thresholds; it does not guarantee that the drive has good latency or that the SATA connection is reliable. Try a different SATA data cable and motherboard port, and make sure the drive is connected directly to the chipset rather than through an add-in controller.
You can temporarily test the power-management theory by setting the active power plan’s AHCI Link Power Management and PCI Express Link State Power Management to a less aggressive setting. If that stops the pauses, update the motherboard BIOS and chipset/storage drivers and then retest. Avoid disabling random services or using system-tweaking tools until you identify the process involved, since Windows itself commonly performs short background disk operations. Also make sure the SSD has free space and, if possible, test it with a sustained write and latency benchmark after backing up important data.
The RAM usage shown is not high enough to explain this by itself. With 32 GB installed and only about 8 GB in use, heavy paging is unlikely. The near-zero throughput alongside 100% active time points more toward latency, retries, or the drive/controller waiting on an operation.