SilverStone Element ST75EF 750 W Power Supply Review
Overload Tests
Contents
Before overloading power supplies we always test first if the over current protection (OCP) circuit is active and at what level it is configured.
In order to do that we removed the peripheral power
connectors from our load tester, making the +12V1 and +12V2 inputs from our tester to match the power supply +12V2 and +12V1 rails, respectively. Then we increased current on each rail up to 33 A (the maximum our load tester is able to go) , but the power supply would still turn on, meaning that either OCP is disabled or configured at a value above 33 A.
Then starting from test five we increased currents to the maximum we could with the power supply still running inside ATX specs. The results are below. When we tried to increase one more amp at any output ripple would go to the roof, meaning that the unit stopped working correctly.
The idea behind of overload tests is to see if the power supply will burn/explode and see if the protections from the power supply are working correctly. This power supply didn’t burn and when we tried to pull far more than it could deliver it would shut down, so this unit passed on this test.
| Input | Maximum |
| +12V1 | 32 A (384 W) |
| +12V2 | 32 A (384 W) |
| +5V | 15 A (75 W) |
| +3.3 V | 15 A (49.5 W) |
| +5VSB | 3 A (15 W) |
| -12 V | 0.5 A (6 W) |
| Total | 906.9 W |
| % Max Load | 120.9% |
| Room Temp. | 46.2° C |
| PSU Temp. | 57.5° C |
| AC Power | 1,246 W |
| Efficiency | 72.8% |
| AC Voltage | 96.8 V |
| Power Factor | 0.999 |