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- HP Community
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- Desktop Hardware and Upgrade Questions
- add additional harddisk to Pro SFF 400 G9

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12-25-2025 11:43 PM
Accepted Solutions
12-27-2025 05:10 AM
If the unit does not already have a 3.5" SATA drive, it would not be difficult to add one.
Here is the manual for that PC
https://kaas.hpcloud.hp.com/pdf-public/pdf_8129740_en-US-1.pdf
Page 22 includes instructions on Removal and replacement procedures.
Replacing the hard drive begins on page 27. Since your PC does not have a SATA drive already, then pick up the procedure in reverse to add the new drive. It should be easy to connect the drive to the SATA port on the motherboard and the power connection.
Here are the SATA ports
Assuming they are both unoccupied, use the SATA0 port. The power is right next to those
or you can use a SATA power connection on the power supply. It will look like this
If the power supply does not have a connector like that, you can use a Molex 4 pin to SATA power adapter
I'm not an HP employee.
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12-26-2025 06:16 AM
It really depends on the configuration of the PC. It shows there can be a M.2
Solid-state drive
2 TB, PCIe-4 × 4, TLC M52027-001
1 TB, PCIe-4 × 4, TLC M16560-001
1 TB, PCIe L85370-001
1 TB, PCIe-4 × 4, TLC, NMIC N22908-001
512 GB, PCIe-4 × 4, TLC M17436-001
512 GB, PCIe-4 × 4, TLC, self-encrypting drive (SED) M52031-001
512 GB, NMIC N24955-001
512 GB L85364-001
256 GB, PCIe-4 × 4, TLC, self-encrypting drive (SED) M52029-001
256 GB, PCIe-4 × 4, NMIC N30732-001
256 GB, PCIe-4 × 4, TLC M52025-001
256 GB L85354-001
128 GB, PCIe-4 × 4 N42382-001
And it can also have a SATA drive
Hard drive
2 TB, 7200 rpm, 3.5 in L89703-001
1 TB, 7200 rpm, 3.5 in, NMIC N03048-001
What is present in the unit you have?
I'm not an HP employee.
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12-26-2025 06:26 AM
Hello,
thank you for the prompt response.
I apologise as my initial query was quite generic.
My SFF PC already has a 500GB SSD and I have 2 external 8TB Seagate drives connected via USB 3.0.
I was trying to add a 3TB HDD internally but I only succeeded in killing my 3TB HDD.
I connected the HDD to the SATA and power ports on the motherboard.
So, I am not sure what I did wrong that I killed the HDD.
Is there any documentation on how to add the additional HDD?
I can only suspect that I must have plugged in the power wrongly.
Again thank you for the very prompt response
12-27-2025 05:10 AM
If the unit does not already have a 3.5" SATA drive, it would not be difficult to add one.
Here is the manual for that PC
https://kaas.hpcloud.hp.com/pdf-public/pdf_8129740_en-US-1.pdf
Page 22 includes instructions on Removal and replacement procedures.
Replacing the hard drive begins on page 27. Since your PC does not have a SATA drive already, then pick up the procedure in reverse to add the new drive. It should be easy to connect the drive to the SATA port on the motherboard and the power connection.
Here are the SATA ports
Assuming they are both unoccupied, use the SATA0 port. The power is right next to those
or you can use a SATA power connection on the power supply. It will look like this
If the power supply does not have a connector like that, you can use a Molex 4 pin to SATA power adapter
I'm not an HP employee.
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12-29-2025 04:39 AM
Glad to help.
Please post back with the progress.
I'm not an HP employee.
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