Why does my BIOS not detect SSD or HDD?

There are a few potential reasons why your BIOS may not be detecting your solid state drive (SSD) or hard disk drive (HDD):

Cables Are Not Properly Connected

First, check that the power and data cables are properly connected to the SSD/HDD and motherboard. Loose or damaged cables are a common reason for drives not being detected. Here are some tips for checking the connections:

  • Make sure the SATA data cable is securely plugged into the motherboard SATA port and the SSD/HDD SATA port. Listen for a click when connecting.
  • Check that the SATA power cable from the power supply is firmly connected to the drive.
  • Inspect the cables for any damaged or bent pins.
  • Try connecting the drive to another SATA port and replacing the SATA cable if you have a spare.

Properly seating both the SATA data and power cables is essential for the BIOS to detect the drive. Make sure the connections are snug.

Drive Is Not Properly Seated in Drive Bay

If the SATA cables are plugged in correctly, another issue could be that the physical hard drive is not properly seated in the drive bay. Here’s how to check this:

  • Remove the data and power cables from the SSD/HDD.
  • Open the PC case and locate the drive in the drive bay.
  • Remove the screws securing the drive in the drive bay.
  • Reseat the drive, making sure it is fully settled in the bay.
  • Replace and tighten the mounting screws.
  • Reconnect the SATA data and power cables.

Pressing firmly to reseat the drive ensures the SATA connectors on the back make good contact. Screws should be tightened snugly but not overtightened.

Drive Is Defective

If you’ve verified the cables are connected and the drive is properly seated, the drive itself may be defective. Here are signs of a defective or damaged SSD/HDD:

  • The drive makes unusual clicking, beeping, grinding or buzzing noises.
  • You receive I/O error messages when trying to access the drive.
  • The drive is very hot to the touch.
  • You’ve recently had a power surge or outage.
  • You’ve dropped or physically damaged the drive.

A defective drive is often the reason a BIOS won’t detect it on startup. Trying the drive in another PC can help confirm if it’s truly faulty. If detected in a second system, the drive likely works fine and the issue is with your original PC.

SATA Mode Not Set Correctly in BIOS

Another possible reason a SSD or HDD isn’t detected is if the SATA operation mode set in the BIOS is not correct for the drive. There are a few SATA modes to be aware of:

  • AHCI: Advanced Host Controller Interface, the standard mode for SSDs/HDDs.
  • IDE: For older optical drives and HDDs.
  • RAID: For setting up RAID arrays with multiple drives.

To check and change the SATA mode in BIOS:

  1. Restart the PC and enter the system BIOS, usually by pressing F2, F10 or Delete during startup.
  2. Navigate to the “Advanced” tab and select “SATA Operation”.
  3. Verify the mode is set to AHCI. If not, change it, save changes and exit BIOS.

Setting SATA mode correctly for your SSD/HDD allows the BIOS to detect the drive properly on restarts. Consult your motherboard manual for SATA mode details if needed.

Drive Not Receiving Enough Power

For high capacity hard drives and SSDs to operate properly, they require a certain amount of power from the PC power supply. If other components in your PC are drawing a lot of power, it can starve power to the SSD/HDD and prevent the BIOS from detecting it.

Check to make sure:

  • The SATA power cable from the PSU is connected directly to the SSD/HDD, not daisy-chained with other components.
  • The power supply provides enough wattage for your full system configuration. A higher watt unit may be needed.
  • The SATA power cable is not damaged or improperly crimped.
  • The power supply is working properly and not defective.

Using a dedicated power cable for the SSD/HDD can help ensure adequate power delivery for detection by the BIOS.

Drive Partition Is Damaged or Corrupted

If your SSD or HDD was working previously but now is not detected, the drive itself could be OK but the partition is corrupted. Common causes include:

  • An improper system shutdown that did not end processes properly.
  • Abrupt power loss that interrupted a drive operation.
  • Filesystem errors or bad sectors on the drive.
  • Drive was disconnected during a write operation.
  • Virus or malware infection.

You can scan the drive using partitioning software to check for errors. If the partition table is corrupted, software can usually repair it. Some signs of partition corruption:

  • You can see the drive in Disk Management but not access the data.
  • The drive shows up as unallocated space.
  • The disk cannot be formatted.

Repairing the partition table may allow the BIOS to detect the SSD or HDD again properly.

CMOS Battery Running Low

The small CMOS battery on computer motherboards provides power to save BIOS settings when the PC is turned off. If this battery starts to die, one symptom can be BIOS settings resetting or drives not being detected properly.

Check the CMOS battery if you have SSD/HDD detection issues accompanied by any of these:

  • BIOS resetting to defaults when power cycling the PC.
  • CMOS checksum errors on startup.
  • BIOS clock and settings resetting.

Replacing the CMOS battery can typically resolve these types of detection issues. The battery looks like a large watch or calculator battery. Make sure to get the right type for your motherboard.

Driver Conflict or Incompatibility

On very rare occasions, incompatible or faulty drivers can cause conflicts that lead to drives not being detected properly at boot. Try these steps if you suspect a driver issue:

  • Uninstall then reinstall the SATA drivers from your motherboard manufacturer.
  • Roll back to an older version of the SATA driver if one is available.
  • Disconnect all other drives except the SSD/HDD having issues.
  • Update BIOS, chipset and storage drivers to latest stable version.

Driver conflicts will generally only occur after making hardware changes like adding drives or installing an OS update. If rolling back or updating drivers does not resolve it, there may be a hardware defect.

Motherboard Has Issue Detecting Drives

In some rare cases, there may be a hardware defect with the system motherboard or its drive controllers that prevents properly detecting SSDs and HDDs on startup.

If you have ruled out all other common possibilities like cables, connections, SATA mode, etc., the motherboard itself may be malfunctioning. Some signs of motherboard issues:

  • Trying known good SSDs/HDDs does not help.
  • Problem started after a BIOS update.
  • Drives work properly if installed in a different PC.
  • Multiple SATA ports have problems detecting drives.

You can contact the motherboard manufacturer for troubleshooting assistance if you suspect a board defect. They may request an RMA to inspect and repair the board if needed.


These are the most common reasons why a BIOS fails to detect an SSD or HDD at startup. Carefully checking the drive connections, power cables, SATA mode, controller drivers and system hardware can help identify and narrow down the source of the detection problem. Ensuring BIOS settings are optimized and updating to the latest firmware versions can also help resolve startup issues.

If drive detection issues persist after trying all applicable solutions, the SSD, HDD or motherboard hardware itself may need to be replaced. Contacting the component manufacturers for RMA servicing can determine if the parts are defective.