PERIPHERAL DRAW

I thought that I would also share the draw of the two peripherals inside my XXHE PC: a single Samsung 840 EVO 750GB SSD; a PPAstudio V1 USB3 card.

Computer State	SSD	PPAstudio V1 USB Card
Computer Off	0.25A	0.02A
Startup	0.44A	0.02A
Playing Music	0.40A to start 0.05A stable	0.01A
Shutdown	0.5A	0.01A

The results were identical when the o/s was minimised and maximised.

The SSD is spec'd at 5V 1.4A (written on drive itself) but I never saw more than 0.5A draw at any stage, although it would almost certainly be prudent to be able to supply the recommended 1.4A to the SSD just in case...we would not want it to lose information if it could not find enough juice.

The builder of the PPAstudio USB card recommends 5V 1A.  The NOS1 does not seem to take usb power at any stage, so perhaps we can get away with powering the PPSstudio card with a higher quality and lower current 5V linear supply.  The USB3 standard gives a maximum load of 0.9mA, and considering that I have been able to measure not more than 20mA draw, perhaps a linear power supply around that 100mA (0.1A) will be perfectly suited if only the NOS1 is connected to the card.

Anthony

TOTAL DRAW OF XXHE PC

I just realised that I had not published the complete draw of my XXHE PC in this thread.  To do this I plugged my pc into the UPS and let the UPS tell me the draw as the pc performed various tasks.

Whole XXHE PC	Minimised o/s	Maximised o/s
Startup	98w	98w
System Idle	58w	68w
Playing Music	68w at start 58w stable	88w at start 58w-78w in a cycle
Shutdown	78w	107w

This information is useful if I end up going a different route with the linear power supply and using a wide range pico psu (eg. 12v - 24v 160w) fed by a single high powered linear power supply.  The pico psu is a tiny dc-dc converter that manages the atx power functions including derivation of the various rails for the P24, P8 and peripherals.  A single 20V 8A supply would be sufficient to run the 160w wide input pico psu.

As you can see from the table above, a 160w wide input pico psu MAY have enough juice to run my XXHE PC, but does it have enough juice to run yours?  This is especially relevant if you run more HDD's or SSD's than me, and use the higher power i7 cpu that is recommended for the XXHE PC.

Anyone care to measure the total draw of their XXHE PC?  I may be able to rule out the pico psu angle if your computers draw much more juice than mine.

Anthony

I have had  look at the tentlabs shunts that you linked.  Why do you think this regulator has not worked for your situation?  Noise and output impedance both seem low.  Perhaps the not-published PSSR and transient response figures were too far out of spec.?  I'm just guessing here, trying to figure out what I should be looking for in a voltage regulator.




Actually, the builder of the PPAstudio USB card recommends a 5V 1A power supply but I can't get my card to draw more than 0.02A into the NOS1, which is 20mA, and is well within 300mA range of the regulator you mentioned above.

I have found an article from Linear Audio Magazine that first measures 15 commercial and diy linear regulators and then does blind listening tests when using them to power a line amplifier.  Although the listening tests are relatively meaningless in the context of the XXHE PC project, the measurements of these regulators could be of some use.  The article itself is not free but the graphs are readily available on their website, so I will reproduce some of them below.  Note the Sjostrom measures well in all three graphs below.  It is interesting to note that one of the 'surprisingly good' regs in the listening tests were the Linear Tech devices which the author of the paper attributed to 'fast transient response'.

Anthony

Thanks Peter,


Wow...righto...I am quite sure that I am not up to the task of designing a linear regulator, I had just assumed that I would be using an existing design and assembling them (at worst) or using an off-the-shelf linear regulator (at best).

For instance, this reg from your part of the world that I could pull out a soldering iron and follow a relatively simple build.  Noise seems fine but the current limit is 1A, so it could only be used to power a USB card or SSD.  I reckon I could build these for about AU$75/50euro each.

5A and 2A loads are going to be much more difficult.

Thanks,

Anthony

Hi Esau,

Please let us know how you go with the PPAstudio card, good or bad.  The more impressions of this product that we get with the NOS1 the better, and if we are lucky a general consensus will emerge and we will have found a reliable cheap upgrade.

I will work through the linear psu thing for the XXHE PC in the coming weeks so keep an eye on that thread.  My audio system with the NOS1 sounds so good right now that I reckon I have plenty of time to thoroughly work through the linear psu stuff and end up with the right power supply in the end.  Who knows, at the end of it all there might be a product that you can build yourself or have someone build for you.

Cheers,

Anthony

EDIT:  I just re-read your post Esau, and I failed to answer one of your questions.  The linear psu project is designed to spec and design a multi-rail linear psu especially for the XXHE PC.  This means that an off-the-shelf supply is probably not going to be either available or suitable for the job so I foresee some kind of diy in my future.  It would be nice if everyone that wants one of the supplies can either make their own or have someone make it for them.

Hi Paul,

I've just fed my PPAstudio card with a cheap lab linear 5v rail...a nice step-up in performance again.  I wonder what a 'good' linear psu would achieve?  I gave a brief rundown of changes the linear psu made over in the linear psu thread.

Cheers,

Anthony

In the sharing spirit, with Paul (Scroobius) having just purchased a PPAstdio USB3 card like mine, I decided to try the lab linear psu feeding said card to see if it makes a difference.

Well it does make a nice difference.  The NOS1 has already outperformed some really good dacs here at home, but it is even better with the PPAstudio card and even a cheapo lab linear psu.  Blacker backgrounds, better 3D imaging, I can hear more of the room in acoustic recordings, or the 'ambience' as Peter likes to put it...the reverb, the echo et cetera.

So mark that up as one rail that is essential to be powered by the linear psu.

Anthony

Thanks Peter,

The power down thing may be a more difficult issue than the power on difficulties.  To do it right some transistor logic will be required using the signal from the motherboard that is transmitted to the power supply via the 'Power On' wire in the P24 ATX socket.  Providing this logic is far beyond my current knowledge so I would have to defer that to others.

A simpler way may be to wait ten seconds or more before turning off the linear power supply or even using a short piece of optic cable to show the status of the mobo lights on the outside of the case so that we can be certain that the mobo has powered down before we cut power to the power supply.

Anyway, I think this is a hurdle for later on down the road.  First we have to figure if the LPSU into the XXHE will make a sonic difference.

Peter, have you got any ideas about good linear regulators to use when building a power supply?  The obvious ones to me are the Paul Hynes regs but they are very expensive and a very long wait time.

Cheers,

Anthony

How to Boot the Asrock X79 Extreme4-M motherboard without an ATX Power Supply

Yep...got it figured out...I can start the Asrock mobo using a three rail linear supply with ZERO help from an ATX supply.

This afternoons efforts have been focused on getting the mobo to boot reliably.  Based on the previous measurements, my 3 rail lab linear supply is not able to provide enough current (from the fixed 5v 3A rail) for the 5v rail of the P24 ATX socket, so I did a little trick to make the BeQuiet SMPS turn on when disconnected from the motherboard thus bypassing its ATX functions.  The BeQuiet SMPS was used to provide power to the P8 CPU socket and the 5v rail for the P24 ATX socket.  The 3 rail linear PSU was used to provide 12v and 3.3v to the P24 ATX socket and 5v to the PPAstudio usb card.

I improvised a wiring loom for the P24 ATX socket that had the three rails (from two power supplies) and grounds distributed as shown in the attached image.  Note that at this stage the grounds don't seem to be too important because everything has worked with my first semi random attempt at spreading the grounds between the three rails.

To get the computer to boot I had to first start the BeQuiet SMPS (12v in P8 cpu, 5v into P24 ATX) and then start the lab linear supply (12v and 3.3v into the P24 ATX socket).  It does not matter how long I wait to turn on the second psu, (I tried from 0.5s to 30s), because the computer fires up every time when I press the power button on the front of the case.  The computer will NOT boot when the BeQuiet SMPS (5v P24 ATX and 12v P8 cpu sockets) is turned on AFTER the 12v and 3.3v rails into the P24 ATX socket.  I am not sure whether it is the 5v rail or the P8 CPU rail or both that must be turned on before the remaining rails into the P24 ATX socket, but that can be determined at a later date.  The important thing is that I can reliably turn the computer on and off with a rudimentary ATX sequencing.

There is one caveat at this stage...for those familiar with the operation of the light on the front power button on the  Silverstone GD06B case...well at this stage I have not spent the time to get that working properly.  It comes on as soon as the 5v rail into the P24 socket is powered regardless of whether the computer is on or not.  The remedy may be as simple as doing something different with the 5v 'Power On' wire into the P24 ATX socket, but I have not spent the time to figure it out as yet.  At this stage the 5v 'Power On' wire is grouped with all the other 5v wires on the 5v rail.

The sequence of events to get the Asrock X79 Extreme4-M motherboard to boot from a non-ATX power supply is as follows:

• Power on the 5v rail into the P24 Socket and the 12v rail into the P8 CPU socket (not sure if both are required to be started first at this stage)
• Following a small delay, power on the 3.3v and 12v rails into the P24 CPU socket as well as other rails to SSD's and USB cards et cetera
• Press the start button on the front of the computer case

Once the computer is successfully shutdown (either by Windows or the power button on the computer case), the order that the rails are turned off does not seem to matter at all for the next boot.  There will be some issue making sure that the computer is fully shutdown before cutting power, so at this stage I think that it will have to be a manual procedure i.e. when windows goes blank after shutdown then turn off the power supply.

Anyway, this took me about 3 hours this afternoon to figure this all out and I am feeling a tad 'special' because I thought it may have taken several weeks on and off, but now we have a way forward for a bespoke FULL linear power supply for the XXHE pc.

Cheers,

Anthony
 

Wow...glad you got one and like it Paul.  Like I said earlier I have not compared my card to the mobo port because of the difference the card made with my previous pc and dac, but I should do that.  If your card burns in like mine it will get to its best at about 200 hours with further extension both high and low.  I have the original V1 card and you would have the V2 card.

On my previous setup this card really improved again with a good linear power supply.

Cheers,

Anthony

Hi Paul,

5v can be provided either from the computers power supply or preferably from a linear power supply or battery.  The maker recommends battery, but I don't want to go down that road, so at the moment I power it from my BeQuiet power supply.  I borrowed a high grade linear power supply in my pre NOS1 days and it certainly made a difference.  Like I said earlier I've not compared this card with the mobo ports with the NOS1 so I can't say if it has any effect, but that comparison is on my list of things to do.

The V2 card is US$129 with international delivery.

Cheers,

Anthony

Hi Nick,

Nice write-up.  I thought that I would share with you some photos of my PPAstudio USB card in the hope that it may give you some ideas or inspiration.  My card is a Version 1 card, not the Version 2.  The V2 is a recent item from Paul Pang that apparently has 95% of the sonic benefits of thie V1 card but is much easier to build which makes it cheaper.

You will notice in the photos the silver transformer and the upmarket TXCO as well as some little blocks of aluminium that Paul places on the card to try to control EMI/RMF a little.  As for the rest of it I am not so sure, but I thought you might have a clue.  I have posted before that this card is well ahead of the SOtM and Adnaco S3B (with linear supply) with my previous dac (I've not compared the mobo port to the PPAstudio card with the NOS1 - maybe I should) and that it can be powered with either the standard PC molex cable or with a linear/battery power supply.  To work the molex socket needs to be populated one way or the other.

Anyway, I hope this is of interest.  I will follow your pursuit with interest.

Regards,

Anthony

Thanks for the kind words Pedal.  I am not yet convinced that better power in the XXHE pc will directly improve anything, but I think that the computers power supply may impact other components via the AC lines.  We will see!

Tomorrow I am auditioning my nos1 in a high end system and if I find some time I will pull out my lab LPS and see if a few of us hear a difference.  I will power the P8 cpu socket, my PPAstudio usb card and the ssd.

Cheers,

Anthony

Yes Peter, please share your drum track. 

And I am with you on the recording quality thing.  It annoys me that some of my favourite music sounds so ordinary.


Anthony

Nice pickup on the 12V rail Peter.  I have checked my notes and edited that post so that it is now correct.


I have shut down all my USB2 and USB3 ports because I use the PCIe USB3 card from PPAstudio.


Oscilloscope's!!  When you want to buy a cheap one they are all too expensive and even then they may generate too much noise to be entirely useful. 

I am enjoying tinkering with this stuff and this is a subject that I have been considering for a while now.  Don't worry though, I am listening to plenty of music.

Cheers,

Anthony