720478-B21: HPE 500W Flex Slot Platinum Hot Plug Power Supply
Also listed as: 754377-001, 866729-001, 723594-001, DPS-500AB-13 A · made by Delta
The HPE 720478-B21 is a 500W Flex Slot Platinum hot-plug power supply engineered for HPE ProLiant Gen9 servers. Offering 80 PLUS Platinum certified electrical efficiency up to 94%, it minimizes data center energy waste while providing tool-less hot-plug replacement and full 1+1 power redundancy.
Specifications
| Part number | 720478-B21 |
|---|---|
| Brand | HPE |
| Made by | Delta |
| Type | Power supplies |
| Other numbers | 754377-001, 866729-001, 723594-001, DPS-500AB-13 A |
| Status | end of sale |
| Wattage | 500 |
| Efficiency | 80 PLUS Platinum (up to 94% efficiency) |
| Form factor | HPE Flexible Slot (Flex Slot) |
| Input voltage | 100V - 240V AC |
| Hot pluggable | Yes |
| Redundancy | 1+1 redundant support |
About the 720478-B21
720478-B21 is the HPE 500W Flex Slot Platinum hot-plug power supply unit designed for ProLiant Gen9 servers. Incorporating 80 PLUS Platinum power conversion delivering up to 94% electrical efficiency, its compact Flex Slot form factor frees valuable internal chassis space for airflow and compute components.
Compatibility
Compatible with all HPE ProLiant Gen9 servers equipped with Flex Slot power bays, including DL380 Gen9, DL360 Gen9, DL560 Gen9, ML350 Gen9, Apollo 4200 Gen9, and SimpliVity 380 Gen9. Also backward compatible with select Gen10 platforms supporting 500W power envelopes.
How to identify a genuine unit
Compact metal module measuring 225mm in length with a dark gray extraction handle, blue release latch, and C14 power inlet socket. Side label indicates option part number 720478-B21, spare part number 754377-001 or 866729-001, and assembly part number 723594-001.
Buying used
Inspect the edge card gold connector blades for burns, pits, or carbon tracking. Check that the internal cooling fan spins freely without bearing grinding noise. Verify that iLO 4 detects the PSU with valid serial number, correct wattage, and normal operating status.
Reference prices (last 12 months, updated 2026-10-27)
Used: USD 24 (1 sighting, Oct 2026)
All sightings
| Seller | Condition | Price | Note | Seen |
|---|---|---|---|---|
| ebay.com | used | USD 24 | Tested working HPE 500W Platinum Flex Slot PSU | 2026-10-27 |
Prices seen on public listings on the dates shown, before tax and shipping. Not an offer.
Fits these models
- HPE ProLiant DL380 Gen9
- HPE ProLiant DL360 Gen9
- HPE ProLiant DL560 Gen9
- HPE ProLiant ML350 Gen9
- HPE Apollo 4200 Gen9
- HPE SimpliVity 380 Gen9
Check compatibility with HPE
Before you buy, confirm the exact configuration against the vendor's own lists: firmware levels, operating systems, adapters and optics that HPE has tested with the HPE 720478-B21.
- Compatibility HPE SPOCK (storage, SAN and host compatibility)
- Part lookup HPE PartSurfer (spare and option part numbers)
- Support HPE Support Center
Equivalent part numbers
- Dell J8YMW Dell 495W EPP Hot Plug Power Supply
FAQ
Can a 500W Flex Slot PSU be mixed with an 800W Flex Slot PSU?
No, HPE ProLiant Gen9 power architecture requires that installed power supply modules have matching wattage ratings for proper load balancing and redundancy.
Is the 500W Flex Slot PSU compatible with standard 110V wall outlets?
Yes, it accepts universal AC input ranging from 100V to 240V with active power factor correction.
Buying or selling 720478-B21?
New, refurbished or used. Tell us the quantity and condition and we connect you with a vetted reseller in your region, usually within one working day.
Sources
- HPE ProLiant DL380 Gen9 Server QuickSpecs - Core Options, checked 2026-10-27