MB pciE VRM question

[m17xr2b]

Hi all, I'm building a passive transport PC so I can send a digital signal to my dac using my lynx l22 pciE 1x card. I already have it set up but I'm wondering if there is a potential for an upgrade with a better motherboard.

So how is PCI-E powered? Is is straight from the ATX connector or is it stepped down with voltage regulators on the motherboard itself? 

[m17xr2b]

Let me put it a different way, does the motherboard change the voltage in any way from the 24pin to power the PCIE slots? From the pinout I see it used multiple 12V and 3.3V pins but I would like to know if they are taken directly from the ATX connector or if the motherboard (re)creates those voltages. 

[wojtepanik]

36 minutes ago, VegetableStu said:

ATX 24-pin yes, in general I think o_o some motherboards have an extra PCIe power connector on them

(wait for confirmation from others though)

eps/atx connector, 4 or 8 pin to the cpu direclty

[.Apex.]

20 minutes ago, m17xr2b said:

Let me put it a different way, does the motherboard change the voltage in any way from the 24pin to power the PCIE slots? From the pinout I see it used multiple 12V and 3.3V pins but I would like to know if they are taken directly from the ATX connector or if the motherboard (re)creates those voltages. 

VRM's are used to step down a voltage, since the Power Supply already provides 12V and 3.3V then there's no need for VRM's, there might be capacitors involved though but i'm not sure.

 

but the PCIE itself can only provide about 75W per specification i think, the rest of the power is taken from the 6 / 8 Pin connectors (Graphics Cards).