Using 2 PSUs?

[darunium]

Hi All,

Building a new rig, and plan on going with the GTX480 for now and if prices drop in a couple of years getting another one for SLI to get a performance boost (or getting a different card in 3-4 years, depending on what seems like the best option at the time).

The power drain from the GTX480 is heinous though, pushing up into the 850-950W range for SLI with even very moderate overclocking (which is all I would do anyway, not planning on OC'ing the CPU at all and only going to push the RAM and GPU slightly if necessary). I'm also of course trying to watch the wallet, which is a problem when there's a huge price jump when you break 650W it seems. To top it all off, I'm looking to keep noise levels down as the computer is for bedroom use. Here's the current rig spec I plan:

CPU: i7-920 or 930
MoBO: Gigabyte GA-EX58-UD5 or something similar
RAM: 3x2GB DDR31600 triple channel Patriot Viper CL8 or OCZ Platinum CL7
HDD: 1x WD Caviar Black 640GB, 1x WD Caviar Black 1TB (upgrade to SSD in a couple years)
Optical: Samsung SH-S223L

GPU: GTX 480 (another in SLI potentially in 2 years), or wait til Q3 to see what comes out
Case: Antec P193
PSU: CP-1000 (only 840W on +12v rails)

So, what I'm wondering is instead of going with the CP-1000, which is ~$130, could I go with a 650W supply for now, which is far cheaper (like the Modu82+), and add an additional PSU if I need more power later.

I saw a few articles on how to do it, but I'm wondering how that actually works out. Do you end up connecting different components to different PSUs? Or is there one output? Does that have any effect on power performance and PSU fan regulation? Thanks!

 

[RadiclDreamer]

I seriously recommend against this

 

[bamacre]

I seriously recommend against this

Agreed. And the odds you'd want to add a second card for SLI are slim. You're likely going to be better off just upgrading to a single faster card.

 

[john3850]

Last time time ran 2 PS blew a new 850xtpe 2004 or 2005.
PS1 MB and cpu PS2 850xtpe the xtpe lasted 1 day bad idea.
Seperate PS for fans pumps lights is cool.
90% of the posts for 2PS were when there was a lack of strong PS.
Main PC has 4890CF fans makes so dam much noise I avoid using it.
Had many sli setups all with water and quiet.
To keep noise down you need water or a underclock.

 

[Meghan54]

So, what I'm wondering is instead of going with the CP-1000, which is ~$130, could I go with a 650W supply for now, which is far cheaper (like the Modu82+)....

You do know that the Enermax Modu82+ you mentioned is more expensive than the CP-1000, right?


And, yes, one can manage two power supplies, but you have to pay attention to the minimum draws each rail on each power supply requires for functioning, otherwise you can end up like john3850 and blow something up.

There are units that have zero amps required on their rails for proper functioning, but some units, esp. older designs, require 0.1-1A on most rails to work properly. Makes a big difference.

 

[Baasha]

Hmm.. strange many are recommending against the use of 2 PSUs.

Check this out:

http://www.youtube.com/watch?v=_f5DAPESLBU

He is using TWO Tagan 1300W PSUs!! D:

 

[yh125d]

If power and cost are so important, why not buy a 5870? Only 15% slower, but 20% cheaper and 65% of the power

 

[HOOfan 1]

Hmm.. strange many are recommending against the use of 2 PSUs.

Check this out:

http://www.youtube.com/watch?v=_f5DAPESLBU

He is using TWO Tagan 1300W PSUs!! D:

Using one of my dad's favorite expressions....if I were going to buy a Tagan BZ 1300, I would buy 2....1 to crap on, and another to cover it up with. Shoddy workmanship galore on those PSUs.

 

[BTRY B 529th FA BN]

Seasonic X 750 Gold will keep you in the highest efficiency % of the efficiency curve with 1 480.

 

[Christoph Katzer]

The CP850 is totally enough for now, even you are planning on SLI now in two years you might even not getting anything compatiple anymore.

So either CP850 or consider the TruePower New 750W.

 

[Rubycon]

Using one of my dad's favorite expressions....if I were going to buy a Tagan BZ 1300, I would buy 2....1 to crap on, and another to cover it up with. Shoddy workmanship galore on those PSUs.

Indeed.

I'm surprised they have not come out with a backplane based PSU system similar to what's used in servers for load balancing and fault tolerance. It would not be cheap but ultra high enthusiast solutions rarely are. (when implemented correctly!)