Seasonic Prime 1300w Question

[vigorito]

Hi, Purchased a Seasonic PRIME 1300W gold PSU recently for my system (Ryzen 9 5900, msi tomahawk x570 ,rtx 3080 suprim x), intending to take advantage of the hybrid mode for silence at idle/low load. However, when the PSU is placed in hybrid mode the fan spins up every 10minutes or so for about 5-7 minutes when the system is idling creating a rather disruptive experience, given the rest of the system is effectively silent,case is lian li 011 dynamic,what i have notice that in the box was only 1x8pin cable (8 wires) and 6x 6+2 pcie cables with 6 wires,my last gx 1000w from seasonic has pcie 3x8pin 8 wires,i used that 2 pcie 6+2 cables (6 wires+1x8pin cable 8 wires for the gpu,could that cause the fan spinning in idle because of some issue with the power on pcis slots,also tried with 3x 6+2 pcie,same fan spinning at idle 

[Juular]

7 hours ago, vigorito said:

Hi, Purchased a Seasonic PRIME 1300W gold PSU recently for my system (Ryzen 9 5900, msi tomahawk x570 ,rtx 3080 suprim x), intending to take advantage of the hybrid mode for silence at idle/low load. However, when the PSU is placed in hybrid mode the fan spins up every 10minutes or so for about 5-7 minutes when the system is idling creating a rather disruptive experience, given the rest of the system is effectively silent,case is lian li 011 dynamic,what i have notice that in the box was only 1x8pin cable (8 wires) and 6x 6+2 pcie cables with 6 wires,my last gx 1000w from seasonic has pcie 3x8pin 8 wires,i used that 2 pcie 6+2 cables (6 wires+1x8pin cable 8 wires for the gpu,could that cause the fan spinning in idle because of some issue with the power on pcis slots,also tried with 3x 6+2 pcie,same fan spinning at idle 

If you're just informing us about this, we know. Almost all Seasonic PSUs use a simple fan controller, there are no hysteresis, so these types of start-stops are inevitable. Most other PSUs targeting the high-end market are using microcontrollers, which can be programmed to provide way smarter control over the fan and other aspects, such as adding protections. There are Seasonic-made PSUs using MCUs, such as NZXT E and EVGA G6, but apparently it's too expensive for Seasonic themselves to sell such designs under their own brand, after all, people are buying them anyway, why bother ?

And if you're seeking an advice on a replacement - see above, that needs to be a separate thread then.

[Skiiwee29]

@vigorito I have split your question out into its own thread so it will get you better visibility to get your questions answered. 

[vigorito]

4 hours ago, Juular said:

 

If you're just informing us about this, we know. Almost all Seasonic PSUs use a simple fan controller, there are no hysteresis, so these types of start-stops are inevitable. Most other PSUs targeting the high-end market are using microcontrollers, which can be programmed to provide way smarter control over the fan and other aspects, such as adding protections. There are Seasonic-made PSUs using MCUs, such as NZXT E and EVGA G6, but apparently it's too expensive for Seasonic themselves to sell such designs under their own brand, after all, people are buying them anyway, why bother ?

And if you're seeking an advice on a replacement - see above, that needs to be a separate thread then.

Okay i get it,but i was using almost 2months seasonic gx 1000 gold (not prime) i have never heard fan while is in hybrid mode how?

[Juular]

1 hour ago, vigorito said:

Okay i get it,but i was using almost 2months seasonic gx 1000 gold (not prime) i have never heard fan while is in hybrid mode how?

That's the thing. Since the fan controler is analogue, it may be different even between different samples of the same unit, not to mention different wattages. In one the passive/active fan mode is set higher, in another one lower, add the lack hysteresis to that and you get start-stops at the verge of that threshold when the load/temperature values are oscillating.

[vigorito]

I allready sold this psu,gonna get 1000w regular gx,which i sold 3 days ago :(, so there is possibility with the new 1000w to get same issue like on 1300w which i didnt have on previous 1000w

[Juular]

1 hour ago, vigorito said:

I allready sold this psu,gonna get 1000w regular gx,which i sold 3 days ago :(, so there is possibility with the new 1000w to get same issue like on 1300w which i didnt have on previous 1000w

Yes. It's possible that your 1.3kW unit just had a manufacturing defect making it's passive/active threshold too low but it's still very much possible with the PSU having an analog fan controller, especially high-wattage one since generally such PSUs have steeper fan curves to compensate for higher thermals at increased 100% load.

So in the end i'd recommend a PSU other than Seasonic Focus or Prime and their rebrands. Corsair RM-x maybe.