$155.99
900 VA / 480 WLine-interactive, Simulated sine
2.9/5
A standby UPS for a mid-range desktop PC when you do not need AVR or an LCD.
- 900 VA / 500 WOutput
- Standby, Simulated sineType
- 12 (6 on battery)Outlets
Check price at Amazon$119.95
Price checked November 9, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- 500 W is enough for a mainstream desktop PC and monitor
- Four widely spaced outlets for large adapters
- Two USB charging ports
Cons
- Simulated sine wave and no voltage regulation
The CyberPower ST standby family
Every CyberPower ST standby model we rank, smallest first. Ratings compare each against its own size.
| Model | Output | Rating | Price |
|---|---|---|---|
| CyberPower ST425 | 425 VA / 260 W | 2.6/5 | $59.95 |
| CyberPower ST625U | 625 VA / 360 W | 2.8/5 | $79.95 |
| CyberPower ST900U (this one) | 900 VA / 500 W | 2.9/5 | $119.95 |
How it scores
The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.
Specifications
| Model number | ST900U |
|---|---|
| Power | |
| Rated apparent power | 900 VA |
| Rated real power | 500 W |
| Topology | Standby |
| Battery waveform | Simulated sine |
| Automatic voltage regulation | No |
| Outlets and features | |
| Outlets | 12 (6 on battery) |
| Format | Desktop |
| Display | LED indicators |
| USB charging ports | Yes |
| Data port, software or network option | Yes |
| Warranty | |
| Warranty | 3 years |
| Connected-equipment guarantee | $125,000 |
Alternatives in this size
$137.70
850 VA / 450 W35 min
Compare
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