865399-101 is the HPE assembly part number for 500W Flex Slot Platinum Hot Plug Low Halogen Power Supply Kit. It is the number printed on the module label and returned by HPE PartSurfer lookups, so it is what you will most often see when identifying a unit already in hand. The module is a hot-plug, redundant Flex Slot plug-in power supply rated at 500 watts with 94% efficiency and 80 PLUS Platinum certification. Input is AC 100-240 volt at 50-60 hertz through an IEC 60320 C14 connector. It measures 2.7 inches wide, 8.9 inches deep and 1.6 inches high, and weighs 32.1 ounces.
HPE Option Part #: 865408-B21
HPE Spare Part #: 866729-001
HPE Model #: 865398-001
HPE Assembly Part #: 865399-101
PRODUCT SPECIFICATIONS FOR 865399-101:
- Product Type: Power supply - hot-plug / redundant
- Form Factor: Plug-in module
- Specification Compliance: Flex Slot
- Power Supply Compatibility: PC/Server
- Power Provided: 500 watt
- Power Capacity (VA): 563 volt ampere per kilogram
- Voltage Required: AC 100-240 volt
- Frequency Required: 50 - 60 hertz
- Input Connector Type: Power IEC 60320 C14
- Efficiency: 94%
- 80 PLUS Certification: 80 PLUS Platinum
- Compliant Standards: BSMI, CCC, CISPR Class A, C-Tick, cUL, KCC, Low halogen, TUV, UL, WEEE
- Width: 2.7 inch
- Depth: 8.9 inch
- Height: 1.6 inch
- Weight: 32.1 ounce
- Min Operating Temperature: 41 degree Fahrenheit
- Max Operating Temperature: 131 degree Fahrenheit
- Humidity Range Operating: 5 - 95% (non-condensing
COMPATIBLE WITH:
PROLIANT DL SERIES
PROLIANT ML SERIES
** This list may not be complete. Contact us via Live Chat if you have any questions about compatibility.
FREQUENTLY ASKED QUESTIONS ABOUT 865399-101
What is the difference between 865399-101, 865408-B21 and 866729-001?
All three identify the same physical power supply. This page, 865399-101, is the assembly part number: the number HPE assigns to the built unit and prints on the module label. 865408-B21 is the option part number used when ordering the kit as a configurable line item, and 866729-001 is the spare part number used for service replacement. The family also includes an OEM model number and an alternate part number, both listed in the cross-reference block on this page.
I read 865399-101 off the label. Is that the number I order by?
Not usually. An assembly part number identifies the physical build of the unit and is what appears on the label and in PartSurfer, so it is the correct number for confirming identity. Ordering is normally done by the option or spare number. An OEM model number, also shown in the cross-reference block, is the base product designation the supply is built to rather than an orderable line item.
Which servers does this power supply support?
This Flex Slot module is listed as compatible with the HPE ProLiant DL360 Gen10, DL380 Gen10 and ML350 Gen10. It installs as a hot-plug, redundant plug-in module in a Flex Slot bay, so it can be added or replaced without powering down a system that has redundant supplies populated. Confirm the server model and Flex Slot form factor before fitting the unit.
What are the electrical and environmental ratings?
The supply provides 500 watts and is rated at 563 volt ampere per kilogram. It accepts AC 100-240 volt input at 50-60 hertz through an IEC 60320 C14 inlet, and is 80 PLUS Platinum certified at 94% efficiency. Operating temperature range is 41 to 131 degrees Fahrenheit with 5 to 95% non-condensing humidity. Compliance includes BSMI, CCC, CISPR Class A, C-Tick, cUL, KCC, low halogen, TUV, UL and WEEE.
Last Updated: 2026-09-01
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This product is warrantied against hardware failure for a period of 1 Year from the date of purchase. Before making a purchase, please take a moment to review our return policy below.
Returns
It is the customer's responsibility to verify compatibility with their machine(s) before placing an order. If an item is ordered by mistake, it can be returned for refund, minus a 25% restocking fee, within 5 business days of receipt. The cost of freight is not refundable.
Please be aware that factory-sealed equipment can only be returned if it remains unopened.
Defective Products
If you have received a defective part and your machine is still within the HPE warranty period, please initiate a warranty exchange by visiting the HPE Enterprise Support Center. Be sure to have the serial numbers of the defective drive and your server/storage array handy.
In case your hardware becomes defective during the Global One warranty period, but the HPE warranty has expired, you can return the product to us for a working replacement. You are responsible for the shipment of returned merchandise. However, we will cover the expense of Ground /Economy shipment for the replacement item(s).
Requesting an RMA
To initiate a return or warranty claim, please complete and submit the RMA Request Form.
