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Question High 12V Rail caused by GPU's

Jun 13, 2020

I am just looking for opinions on a high 12v rail reading I have been getting from my Seasonic 1300w Prime Power Supply.

I have recently discovered using a mult metre and Molex connector that at idle the 12V rail will be at 12.26v and under load this will jump to a max of 12.36. This is within the ATX spec of -+5% however the 12V voltage ripple is pretty high at .1v

I have noticed this only occurs once my 2 GPU's are under load (SLI 2080 Ti's). There is sufficient power being given to these components as the max power draw of the system under load from my testing is 1008W from the wall so well within spec of the theoretical 1300w.

I am just looking for opinions on this as to whether or not I should proceed with a possible RMA or whether or not these readings are sufficient and will not cause any issues down the line. I have not noticed any stability issues so far, I just happened to discover that the 12V rail was running pretty high.

Thank you.
Ripple isn't what your voltage reader reads. So that's not your ripple per se. Your voltage reader only reads the average that is within >500ms of the actual voltage. While ripple can only be read by an oscilloscope set to 50 ms or lower.

It's the behaviour of all Prime series PSU. The Vreg modules were probably set very aggresively by Seasonic so that a high load means a Voltage increase, instead of a sag that happens in most other PSUs. 12.3V isn't anywhere dangerous. You'd need to go above 12.6V and under11.4V to call it dangerous.