Replace Power
Replace Power 280 W ATX power supply for HP A635w A636n A640n A642n A643n A645c A645w A646c
A 280 W ATX power supply with reduced depth for HP desktops, offering 24-pin, 4-pin CPU, three SATA and multiple Molex connectors
- ColorGrey
- TypeATX
- Fans1
- Weight4
- Fits tight HP chassis with 5.86 inch reduced depth
- Delivers 280 watts continuous power for stable operation
- Supplies SATA and Molex connectors for multiple drives
- Runs on 110 or 220 volt mains worldwide
- Low ripple and noise for clean component power
Compatible HP Desktops
This replacement ATX power supply fits HP A635w A636n A640n A642n A643n A645c A645w and A646c models. It uses a reduced depth design to increase compatibility with branded desktop chassis. The unit delivers a total continuous output of 280 Watts with a 420 Watt maximum rating.
280 Watt Continuous Output
The power supply provides 280 Watts of total continuous power across +5V, -5V, +12V1, +12V2, +3.3V, -12V and +5V-SB rails. AC input accepts 110/220V at 47~63Hz. Hold-up time is 17 ms minimum at nominal input and rise time is less than 70 ms.
80mm Fan Cooling
An 80mm fan cools the unit for stability and long life performance. The design achieves low ripple and noise during operation. Hi-Pot testing and ROHS plus CE compliance are included. Dimensions are 5.86" x 3.3" x 4" for a compact fit.
Highlights
- Fits tight HP chassis with 5.86 inch reduced depth
- Delivers 280 watts continuous power for stable operation
- Supplies SATA and Molex connectors for multiple drives
- Runs on 110 or 220 volt mains worldwide
- Low ripple and noise for clean component power
Specifications
| Brand | Replace Power |
|---|---|
| Model | HP A635w A636n A640n A642n A643n A645c A645w A646c |
| Color | Grey |
| Type | ATX |
| Fans | 1 |
| Weight | 4 |
Questions about this item
What does the 280 W total wattage mean for a typical desktop build?
The 280 W total wattage is the continuous power the unit can deliver across all rails, enough for a standard office PC with integrated graphics and a few drives.
Which mains standard does the 110/220 V AC input support in practice?
The 110/220 V AC input covers both 110 V and 220 V networks at 47–63 Hz, so it works worldwide without a voltage switch.
What clearance does the 5.86" depth leave for cable routing in a compact case?
At 5.86" deep the unit is shorter than a standard ATX supply, leaving extra room behind it for cable bends in small chassis.
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