Dual power supply (for higher power, not redundancy)

gommer · Post by **gommer** » Sun Nov 17, 2002 6:45 am

Hi all,

I'm interested in fanless power supply's, but as y'all know they only
come in at 300W total power maximum, which is at or over the limit for
a modern system.

Now for my idea: anyone tried or has given it a thought to use
two of them, for example to power motherboard with everything on it through the first and all other things (all drives) through the second.

Sure this would mean a horrible mismatch in power draw. Other thoughts
on how the power could be better distributed?

Steerpike · Post by **Steerpike** » Sun Nov 17, 2002 9:34 am

It should be possible to buy a device that takes two power supplies as input, and gives out one set of outputs to the system. Our Dell servers at work all have redundant power supplies, and I was poking around inside one the other day. They all go to a 'board', and then from that board, the rest of the system is powered. I would guess this board allows you to actively 'join' the two sources.

Although this is obviously specific to higher-end servers, and probably Dell proprietary, I'm sure someone out there makes a home-grade (cheaper!) version. Good Luck!

gksam · Post by **gksam** » Mon Nov 18, 2002 12:58 pm

What are your thoughts on using like an AT powersupply (since they are pretty cheap to find.. have a manual switch and turn on without any fancy connections) to power up the drives.. and then using the ATX powersupply to power the board? Might be able to run fanless since it has little draw.

gommer · Post by **gommer** » Tue Nov 19, 2002 2:36 am

gksam wrote:What are your thoughts on using like an AT powersupply (since they are pretty cheap to find.. have a manual switch and turn on without any fancy connections) to power up the drives.. and then using the ATX powersupply to power the board? Might be able to run fanless since it has little draw.

Well, i was beginning to take that direction, only I would be happier with a less bulcky solution, somthing like an industrial switched power supply, (only for 12V, which seems to draw the most power). This would be fanless of coarse.
Turning this thing on would not be the problem, since I'll need a relay anyhow to power a pump for watercooling.

I'll be starting another thread too, since i'm a bit puzzeld about the power requirements of a complete system, seems to exist different figures on the web concerning this subject.

ChiefWeasel · Post by **ChiefWeasel** » Tue Nov 19, 2002 3:21 am

Its not difficult to mod two ATX PSUs to power one computer. I have seen an article somewhere, and can look for it if you want it.

PS: Im not sure about the tolerances of the voltages supplied by non computer PSUs, but it might be something worth checking?

gommer · Post by **gommer** » Tue Nov 19, 2002 4:18 am

ChiefWeasel wrote:Its not difficult to mod two ATX PSUs to power one computer. I have seen an article somewhere, and can look for it if you want it.

Great! I would be very happy to see how this should be done. Only hope doesn't suggest equalising through resistors (heat!) or a diode-mixer (voltage drop).

ChiefWeasel wrote:PS: Im not sure about the tolerances of the voltages supplied by non computer PSUs, but it might be something worth checking?

I'll check these off coarse. It's no problem to find things within spec. Prices are reasonable @ ~120$/EUR for 75 Watt.

ChiefWeasel · Post by **ChiefWeasel** » Tue Nov 19, 2002 8:39 am

Ok, there are in fact several ways to do it, so ill just post a link to a search of the [H]ardForum for 'Dual PSU*' here.

Theres load of info there, and there is infact a prebuilt option available from www.overclockers.co.uk i saw a link to!

gommer · Post by **gommer** » Wed Nov 20, 2002 3:06 am

ChiefWeasel wrote:Ok, there are in fact several ways to do it, so ill just post a link to a search of the [H]ardForum for 'Dual PSU*' here.

Theres load of info there, and there is infact a prebuilt option available from www.overclockers.co.uk i saw a link to!

Too bad, can't get through at [H]ardforum (i.e. search takes very long and then eventually returns a completely blank page, also no luck typing the search manually at the forum)

The article I found at overclockers is not for combining PS outputs, it just aids in powering them through the normal single button.

Thanks anyway. I think loadbalancing is the answer, not combing PS's to power the same consumers.

ChiefWeasel · Post by **ChiefWeasel** » Wed Nov 20, 2002 4:01 am

Ok, the search at [H] is more often down that up, but its worth trying again, cos there was lots of info on all types of extra PSUs etc, so you might find something useful.