Power Supply for DIY computer

[michael123]

Hi

 

What are the options today for replacement of (noisy) 160W switched brick power supply 12V ?

We went to upgrade few years old machine with the new motherboard and CPU, and the PC became quite unstable.

Frequently does not boot.

No problems with the original, switched power supply

 

-- Michael

 

[mansr]

What power supply is causing instability? It probably has trouble responding to sudden increases in current demand from the load, even if it can manage a steady supply at the same level.

[michael123]

I was not clear - that power supply (Kora MKIII) worked perfectly non-stop for 4 years. It supposedly had reserve for 25A peak, and 10A minimum 

 

Machine was was somewhat similar to published by Chris, and after few years we upgraded it for new CPU + Motherboard.

Older CPU was 35W, the new one is 65W TDP

 

The question is what do we have market to offer as a replacement for switched PSU?

 

 

[mansr]

1 minute ago, michael123 said:

I was not clear - that power supply (Kora MKIII) worked perfectly non-stop for 4 years. It supposedly had reserve for 25A peak, and 10A minimum 

That peak power still can't be delivered instantaneously. A sudden surge in demand will always cause a brief dip in supplied voltage. The load must either cope with this or ensure it does a gradual ramp-up of current.

 

1 minute ago, michael123 said:

Machine was was somewhat similar to published by Chris, and after few years we upgraded it for new CPU + Motherboard.

Older CPU was 35W, the new one is 65W TDP

TDP is thermal design power, the amount of heat the cooling system needs to remove to keep the system from overheating. It is an average over at least a few seconds. Momentary power consumption will at times be much higher.

 

1 minute ago, michael123 said:

The question is what do we have market to offer as a replacement for switched PSU?

That depends on the requirements. If you name the motherboard and CPU, maybe someone can suggest something from experience. Also, do you have any power-hungry components like hard drives or a GPU?

[Dutch]

Did you check the output voltage of the Kora using a volt meter?

 

If you’re running Windows you could use something like hwmonitor to monitor the 12V voltage rail. If the voltage isn’t near 12V while idling or drops too much when you apply load (eg. using prime95 to stress test) it may either be broken or simply can’t supply enough power or fast enough.

 

There’s not many high quality linear replacement PSU’s to choose from that can deliver the amount of power the Kora can/could. A Paul Hynes SR7 comes to mind which is unobtainable at this moment, a Keces P8 (may be too light), HDPlex 200/400W.

[michael123]

1 hour ago, mansr said:

That peak power still can't be delivered instantaneously. A sudden surge in demand will always cause a brief dip in supplied voltage. The load must either cope with this or ensure it does a gradual ramp-up of current.

 

TDP is thermal design power, the amount of heat the cooling system needs to remove to keep the system from overheating. It is an average over at least a few seconds. Momentary power consumption will at times be much higher.

 

That depends on the requirements. If you name the motherboard and CPU, maybe someone can suggest something from experience. Also, do you have any power-hungry components like hard drives or a GPU?

 

No GPU

Just Gigabyte motherboard, 8700 cpu, 2 x 16G ram, SSD, JCat USB, optical drive

 

The difference is going mainly from 45W 4770T (my mistake above, it is 45W not 35) to 65W

 

The question bis not 'why', I understand more or less.

But what to do now.

Stay with the switched PSU? 

[michael123]

52 minutes ago, Dutch said:

Did you check the output voltage of the Kora using a volt meter?

 

If you’re running Windows you could use something like hwmonitor to monitor the 12V voltage rail. If the voltage isn’t near 12V while idling or drops too much when you apply load (eg. using prime95 to stress test) it may either be broken or simply can’t supply enough power or fast enough.

 

There’s not many high quality linear replacement PSU’s to choose from that can deliver the amount of power the Kora can/could. A Paul Hynes SR7 comes to mind which is unobtainable at this moment, a Keces P8 (may be too light), HDPlex 200/400W.

 

Yeah, I also thought about HDPlex

I remember once Sonore had switched, but very clean PSU

[Dutch]

23 minutes ago, michael123 said:

 

Yeah, I also thought about HDPlex

I remember once Sonore had switched, but very clean PSU

 

Don’t think so. You may have been thinking of SOtM, the SPS-500? This has an SMPS inside.

[michael123]

This one?

https://www.sotm-audio.com/sotmwp/english/portfolio-item/sps-1000/

 

Isn't it weak for our purposes?

[Dutch]

I already edited out the SPS-1000 since it’s linear and you mentioned a switching ps. Only the SPS-500 is an SMPS.

 

Another LPSU I forgot is Uptone Audio’s JS-2 (5A)

[michael123]

They don't fit, I need 12V DC, 13A

 

I saw some monster at TeraDak

[JMotzi]

I have had great experience with the larger HDPlex PSUs and for a full size unit, the Seasonic 600W Fanless PSU SSR-600TLR.  Both are capable of reliable 24/7 service with zero noise and little heat.  HDPlex does a good job of standing behind their products as well.

 

Designing a PC involves a series or compromises with regards to computing power, memory, cooling, component size, overall size and form factor.  Changing out one component for one of a different design could upset the design balance.  Sometimes it is necessary to go for a redesign if a substituted component doesn't work with the others.

 

Here is an example of how I made choices in designing a silent PC to support graphics (not audio) work:  

 

Passively Cooled PC with 65W-CPU & 47W Workstation Graphics

 

For me the no-compromise items were computing & graphics power, memory, reliability and absolutely no noise.  So I had to be flexible on other design elements such as form factor, overall size, aesthetics, etc.  It's not a big machine (smaller than a mid tower) but it's not a tiny console box either.

 

I guess it's a long way of saying that unless you do an exact replacement for your failed brick, you may have to consider a redesign.  BTW, 4 years is a very reasonable life span for a big brick run 24/7.  My experience is that big bricks run 24/7 do need to be replaced from time to time (about 2-3 years).

 

JM

[Superdad]

On 4/6/2019 at 10:14 AM, Dutch said:

Another LPSU I forgot is Uptone Audio’s JS-2 (5A)

 

Thanks, but actually a JS-2 can produce continuous output current  as follows:

5V/5A

7V/6A

9V/6.3A

12V/7.4A (with 120V or 240V AC mains input; lower AC input level will reduce max output capability at 12V—e.g. 220V results in 12V/6.7A max.)

 

Peak capability is much higher but we don’t specify that and caution folks to be skeptical about claims since instantaneous (“peak”) is highly dependent upon defined duration, impedances of supply and cables, and the type of load. [I am oversimplifying a complex topic, but I call BS on a 10A supply that claims “25A peak.”]

[motberg]

On 4/7/2019 at 1:18 AM, michael123 said:

They don't fit, I need 12V DC, 13A

 

I saw some monster at TeraDak

Are you using a DC to DC ATX convertor, like the HDPLEX 400W DC-ATX Converter ?

If using this and your motherboard supports the additional 12V input, you can get 2 Teradak 10 A units

1 18V x 10A for the DC-DC ATX convertor

1 12V x 10A direct to the 12V motherboard EATX

 

I just setup a computer using this on a Z170M-PLUS, 8GB, 65W processor. So far seems the LPS's are loafing along - almost no temp rise from ambient, but I have not yet stressed things...

 

[michael123]

Ar the moment, that's just single 12V 2.5mm input

 

Thanks for the ideas!