Dual Power Supply SLI Setup

[Steveman09]

I'm curious since power demands for my GTX 295 QUAD SLI Setup are so ridiculous if I could just run a 2nd power supply to power just 1 of the GTX 295's?

Just run a separate power supply with the atx connector jumper wired so the power supply turns on and supplies power.

It would be allot cheaper than going out and spending another $250-300 on a 1000-1500watt Monster.

I have a spare 650w Power Supply sitting here so I'm going to give it a try.

Couldn't hurt right? LOL

Anyone else ponder this idea or try it?

 

[Valset]

yes it can depending on your setup. if you don't know what your doing don't do it or just get a dedicated seconded PCIe power booster. I have done it but it requires wiring and some math. (I ran a 8800GTX once like this). its all going to depend on what hardware your using. but really, if you can aford two GTX295 and the rig to drive them why not just pony up for the 1kw PSU? hell even an good 750 would drive them (I would not want to run that long term though)

 

[Steveman09]

yes it can depending on your setup. if you don't know what your doing don't do it or just get a dedicated seconded PCIe power booster. I have done it but it requires wiring and some math. (I ran a 8800GTX once like this). its all going to depend on what hardware your using. but really, if you can aford two GTX295 and the rig to drive them why not just pony up for the 1kw PSU? hell even an good 750 would drive them (I would not want to run that long term though)

Well my issue is, I allready purchased a Corsair 750TX and I was told it was enough, but its having trouble keeping up when I really push the system, I can't return it because its been too long, I just figured why waste $250-300 for a 1k+ PSU when I have another PSU sitting here collecting dust you know?

Plus I think it would be pretty cool to have a second PSU to run various other devices as well.

My case is big enough so I figured why not?

I'm running the Lian LI PC76 so I might as well use some of the empty space LOL

 

[Dangman]

Well which 650W PSU do you have?

But yeah, your plan has been done before. You just need one of these and you'll be set:
http://www.performance-pcs.com/catalog/index.php?main_page=product_info&products_id=21193

 

[Steveman09]

It's a TOPOWER 650w and its got the PCI-E Power Connectors on it.


yeah that y-splitter is exactly what I was talking about.

 

[Dangman]

It's a TOPOWER 650w and its got the PCI-E Power Connectors on it

Hmmm..Which Topower 650W? Some are bad and some are decent.

 

[Valset]

Well my issue is, I allready purchased a Corsair 750TX and I was told it was enough, but its having trouble keeping up when I really push the system, I can't return it because its been too long, I just figured why waste $250-300 for a 1k+ PSU when I have another PSU sitting here collecting dust you know?

Plus I think it would be pretty cool to have a second PSU to run various other devices as well.

My case is big enough so I figured why not?

I'm running the Lian LI PC76 so I might as well use some of the empty space LOL

do remember if you do this that you have to worry about loads with rails and the like, do be careful. I can't tell you about the adapter as i didn't use it (I just wired the second PSU up so that the full load did not come across the two 12v rails.) it works but I can't see it being good.

and for the record a 750XT should be able to run it but like I said its not going to be a good long term solution. it probably puts it pretty close to the max.

Have you taken a KillaWatt reading from the wall as well? before you jump in this might want to see just what your pulling here.

 

[Dangman]

I say the 750TX is not enough considering this review:
http://www.xbitlabs.com/articles/video/display/gpu-power-consumption-2010_3.html#sect0

A single GTX 295 used up to 400W of power when fully loaded. Or 312W during Crysis. So two GTX 295 will use anywhere from 630W to 800W by themselves. Considering that a stock Core i7 920 uses about 130W, even if we were to take the Crysis benchmark as the highest limit, that's 730W to 760W for just the CPU and GPUs alone. So yeah, definitely far past the max rated.