Second Psu

[kaiweiler]

Hey, I'm wonderin if any of use have two PSU's?
I am thinking of taking a smaller one and putting it in the bottom of my case, just to power fans and LED lights and stuff like that, which wouldn't take a whole lot of power.
wondering if this second psu would heat up my case a lot and if it would be possible to maybe remove the loud PSU fans since it would only be powering a few led's and case fans and would not have to work that hard...
Just a thought...

[tesco]

well its certainly possible. you'll wanna relay the on switch so that the secondary psuu powers up at teh same time as the primary one. the one wires are the lite green and any black ground wire on the atx plug that goes into the motehrboard.

as for heat, well it would be adding more into the csae, unlless you make some sort of exhaust for it to go directly out the case. as for the fans, dont remove them, the psu will just get really hot. They normally arent too loud anyway...

[clocker]

I have run two PSUs before.
It's not particularly difficult to set up, but you will need to deal wih the extra heat.
I wouldn't dispense with the PSU fans unless you had an alternative cooling method in place.
You wil also have to arrange for the second unit to get mains power somehow...

[lynx]

As ROSSCO says, use a relay to switch the second psu on.

Here's (http://modtown.co.uk/mt/article2.php?id=psumod) an article which tells you how to get it to turn on, simply replace the jumper wire with a relay. The 20 pin connector is not going to be used at all, so if I was doing that I would desolder the unused wires from inside the psu, leaving just the green wire and one black wire going to the relay. I would probably try to mount the relay inside the psu too, with a molex socket coming out. You can then simply connect it up with a molex plug from your primary psu.

Here's (http://www.unique-hardware.co.uk/article.asp?request=2ndpsu&Page=1) another article which shows some of the techniques and bits of hardware required, but I personally don't think the explanation is as clear.

Mains power should not be too much of a problem either. Simply get a normal power lead and cut the plug off. You need to connect this into your primary supply (a jointing block as shown in the second article is probably easiest). Cut the wires between the back panel/switch and the psu circuit board, join them together again with the jointing block then add the new lead. You can now simply provide mains power to the second psu by plugging the connector into the back.

As you suggested, you can use the second psu for lights and fans, although I wouldn't recommend using it for your cpu fan, but you could possibly use it for optical drives too.

I'm certainly thinking of doing something along these lines myself, although in my case it would be for a peltier rather than flashing lights and buzzers. :lol:

[bigdawgfoxx]

Lights and fans dont take much power...why do you want another PSU?

[clocker]

Well, assuming that you aren't using it to supplement your primary PSU (as Lynx will be doing) the typical reason for a second PSU is to run your critical components
( motherboard and HDD) completely independent of all the other things in the case.

In theory, this might improve the performance of highly sensitive parts (CPU) by stabilizing the power input, but it's hard to tell if that really works....

[ck-uk]

i agree bdf ...i would'nt use two when you cant run it all from one..you save lecky db's heat..

[Z-95]

I use a dual PSU setup on my system. One 200W powers motherboard and cards (b/c video takes LOTS of power) and the other 200W powers 2HDDs, CD-RW, and floppy. Now, I had to do this b/c my system (the one with dual PSU) is OLD!! Specs:
PII 300MHz
128MB RAM
64MB GeForce 2
10/100 NIC
4.1 DSP Sound
Primary HDD: 6GB
Secondary HDD: 40GB 7200RPM
CD-RW: 52x24x52x
Dual PSU: 200W + 200W
Yeah, yeah, its old, but it serves its purpose. This thing is used ONLY for burning CDs, ripping CDs, and Soulseek, so it doesn't matter if its slow. One thing that adding another PSU will do: more fan noise. Running 5 fans in this comp makes my room sound like a windtunnel, it can be heard down the hall! :D Another problem can be where to run the wall power cord. I leave the outside case off mine, so its no problem, I just leave the second PSU outside the case and run wires everywhere (messy, but who cares?:D), but you can also route it through a hole in the back or hardwire it into your existing PSU. If you use an old AT PSU, it is easy to add it, as it had a hardwired on/off switch that you can leave on. However, if you use a newer ATX, you will have to use a relay circuit for the ATX plug (use what lynx said) . Hope this helps! :D

[johnboy27]

Here is a link to the Mysterybyte forum Kai. The guy I bought my OCZ ram from just did dual PSU's in his syatem.There are a couple of threads on there from him. But here is a link to some of it.You may have to register to read tha link though.
http://www.mysterybyte.com/forum/YaBB.cgi?...;num=1083094943 (http://www.mysterybyte.com/forum/YaBB.cgi?board=hardware;action=display;num=1083094943)

[lynx]

Had a rethink about what I wrote earlier, with respect to mains wiring.

Put the secondary PSU in the standard place, and splice into the mains lead inside that one. That way your primary (and presumably more expensive) psu remains unmodified but is simply in a non-standard position.

[clocker]

Lynx,

Based upon my dual setup, I think that you're going to find that leaving either of the two PSUs "untouched" is a difficult thing to do.

Wire management, already a chore with a single unit, becomes an absolute nightmare when two supplies are involved.

Unless you have a very generously sized case I think it's almost inevitable that at least one ( and probably both) units will need to be pruned back severely...

[SingaBoiy]

You can always just leave one on top of the case so it stays cool ;)

[lynx]

Originally posted by clocker@4 May 2004 - 12:51
Lynx,

Based upon my dual setup, I think that you're going to find that leaving either of the two PSUs "untouched" is a difficult thing to do.

Wire management, already a chore with a single unit, becomes an absolute nightmare when two supplies are involved.

Unless you have a very generously sized case I think it's almost inevitable that at least one ( and probably both) units will need to be pruned back severely...
Not if you get those cheap ones which never have enough connections in the first place. :-"

[clocker]

I wasn't referring to the number of connectors so much as the length of the wiring.
My Antec ( see that, Zapjb?) has wiring that is so long I could have my optical drives in another room almost....

[zapjb]

:lol: