What amperage for 19V linear power supply for an audio server?

[cpasmoi]

Hello
after having presented you my project of D.I.Y server I would like to take care of its supply
knowing that I already have the 2 PCI cards,
- Pink Faun USB
- Jcat Net Femto
Serveur Audio D.I.Y

they are powered by a dual power supply in 5 Volt, so it is the rest of the server, motherboard, CPU and 3 SSDs that I would like to connect to a linear power supply 19 Volt which would be connected to the module HDPLEX 400W HiFi DC-ATX and I would need to have your feedback to determine the necessary amperage?
thank you for your answer
cpasmoi

 

[DonH50]

That power supply takes a 19 V DC input? Going by the rating, power is voltage times current or P = V*I. Rearranging, I = P/V so a 400W power supply would need 400/19 = 21 A. But 400W is usually the output so there will be loss; I'd probably look for a 30+ A supply.

Most PC power supplies are SMPS (switch mode power supplies) so not sure how sticking a linear supply in front of that helps... A linear power supply would waste a lot of energy as heat given the low voltages CPUs and logic circuits need, though PCIe cards usually run from the 12 V bus in the computer (plus 3.3 V aux rails).

If it is linear and delivers 12 V at 400 W, that is a drop of 7 V across the regulator so would waste 7 V * 21 A = 147 W at full power, quite a lot of heat. If the output is 400 W at 12 V that is 33.333 A so the input power would be 633 W and 60% (233 W) is lost as heat. Ouch. That is why SMPS have become so popular, as they waste only about 10%, and their high switching frequency puts all their noise well above the audio band instead of right in the upper bass and low midrange.

HTH - Don

 

[uschi]

That is why SMPS have become so popular, as they waste only about 10%, and their high switching frequency puts all their noise well above the audio band instead of right in the upper bass and low midrange.

HTH - Don

i was just planning to go from smps to lps for my pc.
so do you think thats not even better sonicwise?

 

[DonH50]

i was just planning to go from smps to lps for my pc.
so do you think thats not even better sonicwise?

Could be better, could be worse. It depends upon the rest of the system. Generally I'd expect it to have no impact since the voltage is further regulated by the sound card or sound system before reaching your ears. Any negative impact, from a linear or SMPS, is likely due to a weakness someplace else, like poor power supply regulation, poor noise (EMI/RFI) immunity, unintended ground path, and so forth.

But the linear supply will add a lot of heat, and heat not only increases noise, it shortens the life of electronic devices.

However, we tend to hear what we want or believe, so you may hear an improvement even if it is not really there, and thus increase your personal satisfaction with your system. That is outside my area but very real.

 

[Addicted to hifi]

i was just planning to go from smps to lps for my pc.
so do you think thats not even better sonicwise?

Welcome uschi to wbf.

 

[Alrainbow]

welcome .
300 watts is good in most cases unless your a big fan of up sampling . an lps will sound better HDPLEX has good line up to use . they make a 300 watt unite and a 400 watt dc to dc atx baord . it connects to your mainboard .
now let me add this . the HDPLEX has several outputs to use . 19 volt non variable is used for the dc to dc board . it does have plugin dc cables to supply 12 and 5 volt on one buss . if you plan to use pci cards use the wire adaptor it comes with for had drive used for the os hard drive . it has both 12/ 5 volt for hard drives . then use the supplied adaptor's for the pci cards be it 12 volts or 5 volts needed . if you plan to use additional drives for music non OS use another 5 volt port . i assume your planning on ss drives .
if you plan to use a sw mod supply buy the best one based on specs not just power . i use a good exp sw mod on my nas , if i use it on my server for music you can hear a sound degrade compared to an lps unite

 

[Alrainbow]

https://hdplex.com/hdplex-fanless-300w-linear-power-supply-for-pc-audio-and-ce-device.html
lps psu

HDPLEX 500W HiFi DC-ATX

Support CableMod Silverstone ATX Modular Cable ST Series and NFC Skywire ATX Cable 2.0 HDPLEX 500W HiFi DC-ATX Enjoys Free Shipping Worldwide Stock Status USA : In Stock Germany : In Stock UK : In Stock ASIA : In Stock Australia : In Stock

hdplex.com

dc to dc atx 400 watt

 

[cpasmoi]

Hello

Finally I connected a linear power supply 19 Volt 6 Amps or 114 W on the HDPLEX 400W HiFi DC-ATX converter and no problem, I sample in dsd 256 with hqplayer desktop and no problem, the server has no cut, it has a CPU Ryzen 7 5700 G powerful enough with a TDP of 65 W which makes it an excellent tool for convolution too
the 2 PCI cards, JCAT NETCARD XE and the USB Pink faun are on a linear power supply also 2* 5Volt

Sincerely yours

cpasmoi