What about having more than one PCIe USB controller card in the Audio PC ?

[AlainGr]

Hi Peter,

My question may be silly, but if I was to install more than one PCIe USB controller card in my Audio PC, but have only one of them activated at the same time, will it draw current and potentially affect SQ ?

The reason is that I have a few PCIe cards and would like to compare them, but without having to insert and remove each of them.

I would simply deactivate them in the Device Manager, letting only the one I wish to use. Then I would deactivate this one an activate the other...

Do you consider this to be an heresy or is it acceptable - at least I will proceed that way for a while... ?

Yes, I think it is a silly question, but...

Regards,

From the "Uh ?" guy that is freezing in Canada (maybe I got the brain freezed too)

Alain

[PeterSt]

Hi Alain,

Is not such a silly question ...

The driver won't be doing anything if you switch it off in Device Manager, so the OS is not bothered by it (no interrupts and such). But current it will draw as there won't be anything that switches off the card electrically. Oh, maybe some transceiver chip won't be active (nothing to receive or transmit) but the card will be on.
Is that bad ?

We say that everything matters and probably it does. But what will be going on with this is a contiuous (small) current draw, hence not spikey. So I guess it is fine.

One other thing, not often discussed explicitly :
Any device drawing from the mains will lift the ground potential (DC Offset) of the mains somewhat. Thus, the more toasters and phone chargers and what not you have on the mains, the more the DC Offset will change. And you can see this when you can - and know how to measure it (can is already difficult because it requires a separate mains earth to see it). This influences the sine wave of the mains power.
So I think it would be true that your few mA drawing extra USB card, also influences that. Very miniscule of course, but still.

Best regards,
Peter

[AlainGr]

Thanks Peter, it will not be for a long time, just to make comparisons.

It's the Sotm PCIe USB 3 card that I'd like to test again. It should allow me to power it easily with a LPSU (it has a connection for this).

If this brings good results, I may ask how to power the Silverstone USB card that many of us use but I guess it will requires more effort to have it done.

Regards,

Alain