I recently bought a 4TB Seagate OneTouch portable HDD and wanted to test it before using it. Windows shows the expected capacity of about 3.7TB, but SeaTools and GSmartControl identify it as roughly 16TB. The drive name also looked unusual at first and later changed to something resembling a Hitachi model name.
SeaTools' long generic test stayed at 0% for about 30 minutes, and its short tests caused the drive to disconnect completely. GSmartControl behaved the same way. I tried different USB 3 ports and cables with no improvement. CHKDSK /r does not disconnect, but it has been running extremely slowly—around 1% per hour—even though the drive is empty.
System information identifies the device as an older 5400 RPM Hitachi Travelstar with a reported capacity that conflicts with both the 4TB Seagate packaging and the Windows partition size. Is this kind of testing speed normal, or are the conflicting identities, incorrect capacity, and disconnections signs that the drive is counterfeit, misidentified, or defective? I still have 14 days to return it.
3 Answers
The 3.7TB shown by Windows is normal for a marketed 4TB drive, but diagnostic software reporting about 16TB and identifying a Hitachi disk inside a Seagate enclosure is not normal. It could be a swapped or refurbished disk, altered firmware, or a failing USB-to-SATA bridge. Disconnecting whenever diagnostic tests begin reinforces that something is seriously wrong. I would stop CHKDSK, avoid writing any data, and return the drive for a refund or replacement.
I would return it rather than spend more of the return period testing it. A healthy 4TB drive should not take several days to scan with CHKDSK /r over USB 3. That command reads every sector, but roughly 1% per hour suggests repeated read timeouts or retries rather than normal slowness. The changing Hitachi identification and reported 16TB capacity are also major red flags. Check whether the physical serial and model information match what the diagnostic tools report, and describe the mismatch when requesting the refund.
A long surface scan can take many hours on a large mechanical disk, especially through USB, but an empty 4TB drive progressing at about 1% per hour is excessive. Since multiple diagnostic programs produce the same disconnect behavior and the device reports contradictory hardware details, this is not a drive I would trust with data.
The 5400 RPM speed alone would not explain the extremely slow scan. The inconsistent identity and capacity are much more concerning.