Replace Power
Replace Power 420W ATX power supply grey 1 fan 20+4Pin 12V 16A 250W replacement
420W ATX replacement PSU with 20+4Pin and +12V connectors for Bestec 250W units
- ColorGrey
- TypeATX
- Fans1
- Weight0.1
- 420 W output upgrades from 250 W original
- Single 12 V rail delivers 16 A for stable loads
- 20+4-pin ATX connector fits existing motherboard
- 115 / 230 V input works worldwide without switching
- Grey ATX chassis with one fan keeps system cool
Replacement 420W ATX Power Supply
This 420 watt ATX unit replaces the Bestec ATX-250-12Z C5R 250W and compatible HP models including 440569-001 and HP-D3057F3H. It delivers a free capacity upgrade over the original 250 watt design while using the same 20+4 pin main connector and single +12V rail rated at 16 amps. The grey chassis houses one fan and weighs 0.1 units.
Suits owners of legacy HP desktops needing
Builders restoring or repairing systems that shipped with the listed Bestec or HP part numbers will find the connectors and form factor match without modification. It is not for systems requiring higher 12V current than 16A, multiple 12V rails, or modern CPU and GPU power connectors not present on this unit. Buyers needing greater total wattage or modular cabling should look at other models.
Fits standard ATX bays with 115/230V input
The supply accepts 115 or 230 volt input at 50 or 60 Hz and provides +3.3V at 13A, +5V at 13A, -12V at 0.8A, -5V at 0.5A and +5VSB at 2.5A. Rise time is under 70ms and hold-up time is at least 17ms at nominal voltage. The single 20+4 pin connector feeds the motherboard while the integrated cables serve legacy peripherals, freeing the builder from sourcing obsolete proprietary parts.
Highlights
- 420 W output upgrades from 250 W original
- Single 12 V rail delivers 16 A for stable loads
- 20+4-pin ATX connector fits existing motherboard
- 115 / 230 V input works worldwide without switching
- Grey ATX chassis with one fan keeps system cool
Specifications
| Brand | Replace Power |
|---|---|
| Color | Grey |
| Type | ATX |
| Fans | 1 |
| Weight | 0.1 |
Questions about this item
Does this 420W unit need a 20+4-pin motherboard connector and a +12V rail rated at 16A to power my system?
Yes, it supplies a 20+4-pin main connector and a single +12V rail delivering 16A, matching the listed output specification.
Will the grey ATX chassis and single fan fit the same mounting points as my old Bestec ATX-250-12Z C5R 250W supply?
The unit follows the ATX form factor and is described as a direct replacement for the Bestec ATX-250-12Z C5R 250W and HP 440569-001 models.
How can I verify the PSU is operating correctly once installed?
Check that the system powers on reliably, voltages on the +3.3V, +5V and +12V rails remain stable under load, and the single fan spins without unusual noise.
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