Ripple
Noise and Ripple can easily be measured by an oscilloscope. These show how much voltage fluctuation there is on a particular rail. We tested the rail stability of the 3.3 volt, 5 volt and 12 volt rails using an identical time and millivolt scale for all graphs. millivolt ripple is measured by the peak to peak size of the voltage curve.
The latest ATX 12 volt version 2.3 specifications state that ripple from peak to peak must be no higher than 50 millivolts for the 3.3 volt and 5 volt rails, while the 12 volt rail is allowed up to 120 millivolts peak to peak to stay within specifications. Millivolt figures are stated to the closest increment of 5 given their variability.
| Load (%) | 3.3V Ripple | 5V Ripple | 12V Ripple |
| 20 | 15 | 15 | 20 |
| 40 | 15 | 20 | 20 |
| 60 | 15 | 20 | 25 |
| 80 | 20 | 20 | 30 |
| 100 | 20 | 25 | 30 |
Teapo are high quality? Things have certainly changed since the days I used them.
When I worked on the bench back in the mid 80’s to late 80’s repairing switching PSU’s was my job and Teapo were a cheap and nasty brand of cap we used to buy use because they were far cheaper than Nippon Chemi-Con and a lot easier to obtain. Generally they were good for about 9 months then they began to swell, leak and pop but those PSU’s were not PC PSU’s but heavy duty PSU’s used in large mainframes, in fact so much current ran through them that they buzzed and it was nerve wracking to to thread a screwdriver past the heatsinks and exposed coils to tweak a potentiometer.
Anyway I’m rambling on now. What I’m getting at is Teapo have been around for a long time and I guess their components have improved considerably because a lot of reputable manufacturers use their caps.