2x650W = 1300W psu for X1800/X1900CF/SLI ?

For folks with dual core/sli or cf rigs, how you doing that with 7800gtx sli and x1800xt cf ?

I'm thinking of using this

http://www.coolpc.com.au/catalog/images/2097807533.jpg

http://www.coolpc.com.au/catalog/pro...roducts_id=630

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This adapter cable allows you to run a secondary ATX Power Supply without the need for a second ATX plug on the motherboard. The main power supply simply plugs into the molex connector on the adapter cable, which then supplies the On/Off signal to the secondary ATX PSU via a female 20-pin ATX Cable.

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similar one for non-Aussies http://www.performance-pcs.com/catal...oducts_id=3163

with 2x 650W Silverstone SLI psu http://www.silverstonetek.com/products-65zf.htm

i read there might be dangers with ATI cards doing this but not 7800GTXs ? do X1800XT/X1900XT/XTX ATI cards have any issues ?

how have you got them connected up ? both cards on 2nd psu or 1 video card on main psu and other video card on other psu ? drives and fans off main or 2nd psu ?

looking to add more grunt as i have 2x 650W Silverstone SLI psus here lying around... and 1KW PC Powercooling just landed in Aussie store but too expensive at AUD$795 = US$597 vs 650W Silverstone SLI at AUD$185/each

I have FX-57 0516WPMW and dual core opteron 170 waiting for phase change unit to be completed so thought i'd plan ahead

Motherboards plan to use

DFI NF4 UT SLI-DR
DFI NF4 Ultra-D
Abit AT8 Crossfire

thanks :)

George

That's an amazing tool... I was wondering about that issue cause I want to hook up another PSU too whe I switch to watercooling...

NC™

If you use this just to power your graphic cards, as an example, are the molex's on the cards (12v's) in common with of the 12v's, or grounds on the motherboard (via the pci-e slot)?

If things are in common, you might get some funky things going on if the each power supply has different voltages on it's rails, and they might also vary more under loads, ect.

of course this is just a thought, since i have no clue, and am not sure what is in common between MB and other components (video cards). Just stuff to think about.

yeah i'm really unsure as i just found the ATI thread i was looking for http://www.xtremesystems.org/forums/...ad.php?t=41220

Heh, after reading that thread i wish you luck. All that little connector does is only turn on the secondary power supply if the first psu is on (like a remote turn-on for a car stereo - for the amplifiers). Too bad you can't get schematics of motherboards and videocards, for some piece_of_mind!

I should have a second PCP&C 510 coming to me soon so I'll be running 2x510 = 1020W...I'll be sure to let you know how it goes....

some very interesting things could be happening with these as they are not electrically isolated which means you could potentially create faults and such... not too sure as im only a sophomore of studying crap like this..but depending on the ground and how they are looped this could be ugly..

however from the simpleness of it. i'd say it is just a jumper wire with 2 molex's on it.

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Originally Posted by bullet2urbrain

however from the simpleness of it. i'd say it is just a jumper wire with 2 molex's on it.

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I think the the connector just uses the 12V or 5V of the 1st PSU (one connected to mainboard) to power a relay, which connects the green wire (power on?? i forget the exact name) to ground - which turns on the 2nd psu via the atx connector of the harness. At least is what i get out of the picture and description.

I use an OCZ 520 system and an OCZ 420 for the GT's and zalman coolers. I glued the jump start wire in the molex and I'm good 24/7.

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Originally Posted by afireinside

I use an OCZ 520 system and an OCZ 420 for the GT's and zalman coolers. I glued the jump start wire in the molex and I'm good 24/7.

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Really? Wow, I had always thought it was bad to run two PSU's together unless one is just powering fans hard drives and other components not intertwined with the mmotherboard voltage supply.

I remember this back in the 9800pro days when some guy fried his card since it was running off a different PSU than the Mobo.

i did it for a while... but you have to make sure they are electrically isolated...

if they share a ground or they come in contact.. bad things will/can happen.

fans/watercooling/optical drives are no biggie.

Useless to drop money on those, ALOT easier to merely hard wire them.

Just connect the Green (power on) wire and a ground to Both PSU's and they'll boot togther. Been using that method since I bought my Full-Tower and I never plan on going back. :D

Ah, What the hell, I got bored and pulled out the camera. :cool:

(Be back in a moment, Going to take a picture or two.)

just put the jumper wire in yourself.

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Originally Posted by ShawnMcGrail

Useless to drop money on those, ALOT easier to merely hard wire them.

Just connect the Green (power on) wire and a ground to Both PSU's and they'll boot togther. Been using that method since I bought my Full-Tower and I never plan on going back. :D

Ah, What the hell, I got bored and pulled out the camera. :cool:

(Be back in a moment, Going to take a picture or two.)

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I have the diagram of this from years back, from OCUK or OC.com or something I think..

subscribed. Someone should shoot ATI a e-mail about this.

hey George
i have that exact item, and yes its bought from coolpc...

very handy for dual psu setup, the only question maybe sometimes the second psu wont power off....

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Originally Posted by Victorshen

hey George
i have that exact item, and yes its bought from coolpc...

very handy for dual psu setup, the only question maybe sometimes the second psu wont power off....

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thank guys for the feedback..

Victorshen, that could be a problem if you read http://www.xtremesystems.org/forums/...ad.php?t=41220 but that's for a different ATI model of card... so confused as always heh

I still maintain that a pcp&c 510 SLI will run anything out now and in the next year at least most likely 2

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Originally Posted by eva2000

thank guys for the feedback..

Victorshen, that could be a problem if you read http://www.xtremesystems.org/forums/...ad.php?t=41220 but that's for a different ATI model of card... so confused as always heh

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i thought it would be wise to have a DMM to measure the output volt first and keep one psu to power up the mobo + vga and the other to handle hdd+fans.....

coz i really dunno what will happen if different volts (say 11.8v & 12.2v) are applied to mobo and vga cards....

I have the CM stacker and it comes with a connector similar to the one pictured above. I have not used it as I have not had power issues yet.

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Originally Posted by J-Mag

Really? Wow, I had always thought it was bad to run two PSU's together unless one is just powering fans hard drives and other components not intertwined with the mmotherboard voltage supply.

I remember this back in the 9800pro days when some guy fried his card since it was running off a different PSU than the Mobo.

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7800s and x1800/x1900 I think regulate their own power. Works fine. 9800s and x800s didn't.

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I still maintain that a pcp&c 510 SLI will run anything out now and in the next year at least most likely 2

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Of course it will. I can run SLI + dual core on an OCZ 420. When you bring balls to the wall overclocking into play, you need all the power you can get.

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Originally Posted by computerpro3

I still maintain that a pcp&c 510 SLI will run anything out now and in the next year at least most likely 2

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Running and performing are two totally different things ;)

One thing I know works with the DFI boards is plugging one supply in to the ATX and 8pin connector. That supply will power the board and all other components (minus the SLId vid cards). Then plug another psu into the floppy connector near the PCI-E slot. This supply will power the video cards only. When the board powers up off the main supply, the secondary fires up as well since it is plugged into the 4 pin floppy connector onboard. So, the secondary is providing current for the SLI action as well as being plugged into the cards.

Not a perfect solution, but a solution untill hard-wiring is figured out.

I feel like I am starting to get close to maxing out my 510 SLi w/ OC this FX60 and all the other crap on my system. I'm thinking PCP&C 800 or 1000. Do you guys think the 1000 is overkill?

Here's a wattage calculator I found:http://www.extreme.outervision.com/index.jsp

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Originally Posted by Hell-Fire

One thing I know works with the DFI boards is plugging one supply in to the ATX and 8pin connector. That supply will power the board and all other components (minus the SLId vid cards). Then plug another psu into the floppy connector near the PCI-E slot. This supply will power the video cards only. When the board powers up off the main supply, the secondary fires up as well since it is plugged into the 4 pin floppy connector onboard. So, the secondary is providing current for the SLI action as well as being plugged into the cards.

Not a perfect solution, but a solution untill hard-wiring is figured out.

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Wouldn't that be bad for the board? With two different rails on it? One @ 12.2v and one at 12.8v for example with 2 different PSUs?

hrmm. the video card power seems off. Since they dont have x1800/1900 CF on there i used the GTX512 SLI in its place with Everything im currently running in my box and it only came out to 560w 100% peak with my 148 running 3ghz@1.6vcore. I hope its right then i could most likely get away with my ocz520adj.

it can be.

really depends how the voltage regulation of the video card is.

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Originally Posted by Victorshen

i thought it would be wise to have a DMM to measure the output volt first and keep one psu to power up the mobo + vga and the other to handle hdd+fans.....

coz i really dunno what will happen if different volts (say 11.8v & 12.2v) are applied to mobo and vga cards....

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yeah it's looking like best way is to power cards on main psu and other stuff off 2nd psu would that be enough for X1900 CF setup with Opteron 170 dual core cpu on phase eventually ?

my current setup

Opteron 170 CCBWE 0546XPMW
DFI NF4 UT SLI-DR R.AB0 1114-3 bios
2x 256MB BFG 7800GTX SLI stock HSF with HeavyH20 stock bios set 473(525)/1350
2GB OCZ PC4000EB Platinum 3-3-2-8 rated ram
4x 80GB Hitachi 7K80 SATAII Raid 0 OS drive
1x 250GB Maxtor Maxline Plus II PATA
Pioneer DVD Burner
Floppy drive
510W PC Powercooling SLI PSU

I been using dual ocz 600w's for a while now with both my 7800-256 & 512 GTX
cards in SLI. Second ocz 600w psu is jump started
(black-green 24 pin atx male connector).
Works well this way. :)

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Originally Posted by afireinside

Wouldn't that be bad for the board? With two different rails on it? One @ 12.2v and one at 12.8v for example with 2 different PSUs?

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I am no positive on this, but I would think that the additional 4 pin connector is on a seperate circuit that is used just to add more stability/current to the PCI-E ports versus the main power circuitry running through-out the board as a result of the main psu being plugged into the ATX and 8pin aux connectors. Regardless of the seperate 12v rails being different voltages shouldnt matter.

It certainly isnt bad for the board on the short end as I recently did it, albeit by mistake. I was testing a psu and didnt realize I hadnt unplugged my main psu from that 4 pin connector near the PCI-E port. Worked fine, but again that was not run that way for extended periodsl. Maybe an hour or so of FEAR.

I am just getting into this side of A64, so still picking up things here and there. Still have to look over the power circuitry of the board as a result of the added 8 pin and 4 pin connectors.

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Originally Posted by s7e9h3n

Running and performing are two totally different things ;)

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Okay, I still maintain a pcp&c 510 SLI can perform as equal to or better than 2 power supplies put together on any of today's configs.

Remember, this is a power supply WARRANTIED to maintain 1% voltage tolerance in a Dual core/CPU, SLI system with up to 11 hard drives.

I've had lengthy discussions with Larry, the head engineer at pcp&c multiple times; the quality of componets this thing is built with is something else. Ask hipro if you don't believe me. Also do not forget they are rated at 50C, which means there simply is no derating curve.

Dual power supplies at present times except in server configurations will have no advantage to overclocking over a pcp&c 510 sli, or possibly an OCZ 600w. If you don't believe me, buy a kill-o-watt meter; none of our computers pull 650w from the wall, which is what the pcp&c will do 1% tolerance with. You'll be lucky to hit 500w.

OCZ 520 ran X1800 CF setup with 3.7Ghz FX-57 and a big ass 120MM Sunnon fan for me perfectly.

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Originally Posted by computerpro3

Dual power supplies at present times except in server configurations will have no advantage to overclocking over a pcp&c 510 sli, or possibly an OCZ 600w. If you don't believe me, buy a kill-o-watt meter; none of our computers pull 650w from the wall, which is what the pcp&c will do 1% tolerance with. You'll be lucky to hit 500w.

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Tell that to my computer that would randomly crash with a single OCZ 520 until I added a 420 for the video cards. Even if a single PSU CAN run the system, dual will give you more head rooom and possibly a higher max clock with extreme cooling. If it doesn't help, well it's still nice to think it's doing something ;)

Oddly enough my system is running perfectly on an enermax liberty 500 watt... Go figure.

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Originally Posted by computerpro3

]
Dual power supplies at present times except in server configurations will have no advantage to overclocking over a pcp&c 510 sli, or possibly an OCZ 600w. If you don't believe me, buy a kill-o-watt meter; none of our computers pull 650w from the wall, which is what the pcp&c will do 1% tolerance with. You'll be lucky to hit 500w.

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It's not quite as simple as just hooking up a kill-o-watt. How that power gets allocated is far more important. For our usage, we generally need very heavy current on the 12v rails. Dual rails generally aren't much help, since they just tend to split into two relatively low amp rails. Even though you'd be drawing about 500w tops from the wall, I think its fairly intuitive that two beefy +12v rails are going to help you out a lot, even though you wouldn't be using anywhere near the 1000W+ you could theoretically get with a couple of heavy supplies.

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Originally Posted by computerpro3

Okay, I still maintain a pcp&c 510 SLI can perform as equal to or better than 2 power supplies put together on any of today's configs.

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That's why I'm about to run 2 x 510 PCP&C 510 SLI's ;)

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Originally Posted by s7e9h3n

That's why I'm about to run 2 x 510 PCP&C 510 SLI's ;)

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And why do i bevive that from you...:stick: :toast:good luck but just use the jumper trick with the green line and grouns on the ATX plug...

Dragon

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Originally Posted by G H Z

OCZ 520 ran X1800 CF setup with 3.7Ghz FX-57 and a big ass 120MM Sunnon fan for me perfectly.

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Strange. R520 XF requires 38A on 12V. But OCZ520 gives only 33A. :confused:

Have you looked at the FSP Epsilon range. 4x12v @ 15A each. Combine to something like 50A 12v. Cheap as well, £85 in the UK

http://www.ocheaven.com/readvarticle_en.asp?id=1310

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Originally Posted by Cooper

Strange. R520 XF requires 38A on 12V. But OCZ520 gives only 33A. :confused:

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They are assuming 38a at 20C. OCZ is rated at 40C, pcp&c is 50C.

Therefore ratings on OCZ and PCP&C go a hell of a lot further than other companies. Same goes for FSP group. Generally it is close to a 30% de-rating curve for both watts and amps, which varies depending on quality of componets used.

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Originally Posted by fornowagain

Have you looked at the FSP Epsilon range. 4x12v @ 15A each. Combine to something like 50A 12v. Cheap as well, £85 in the UK

http://www.ocheaven.com/readvarticle_en.asp?id=1310

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IIRC, the Antec Neo 500 has 3x17A 12V rails = 51A, but it doesn't mean that the psu can/will supply that much amperage continuously.....

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Originally Posted by computerpro3

They are assuming 38a at 20C. OCZ is rated at 40C, pcp&c is 50C.

Therefore ratings on OCZ and PCP&C go a hell of a lot further than other companies. Same goes for FSP group. Generally it is close to a 30% de-rating curve for both watts and amps, which varies depending on quality of componets used.

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Don't forget Zippy @ 50C as well ;)

yup

Fortron are rated at 40/50c, or used to be.

The new PSU's that seem to be more bling might be lower.

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Originally Posted by Hell-Fire

One thing I know works with the DFI boards is plugging one supply in to the ATX and 8pin connector. That supply will power the board and all other components (minus the SLId vid cards). Then plug another psu into the floppy connector near the PCI-E slot. This supply will power the video cards only. When the board powers up off the main supply, the secondary fires up as well since it is plugged into the 4 pin floppy connector onboard. So, the secondary is providing current for the SLI action as well as being plugged into the cards.

Not a perfect solution, but a solution untill hard-wiring is figured out.

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Can you elaborate? What floppy connector are you talking about exactly? Maybe a picture w/the connector circled would be nice.

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Originally Posted by 5150 Joker

Can you elaborate? What floppy connector are you talking about exactly? Maybe a picture w/the connector circled would be nice.

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http://www.fileshosts.com/DFI/NF4_SLI_D/web/NF4_020.JPG :)

anyway went with 1KW single psu instead so far so good http://www.xtremesystems.org/forums/...ad.php?t=88695

http://fileshosts.com/psu/PCPowerCoo...kw_psu_023.JPG

:woot:

what a beast :D

I wish I could fit that 1000w beast in my case:( I'd already have one if I didn't have a space issue. I'd take a single 800 or 1000 pcp&c over a double psu set up anyday.

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Originally Posted by eva2000

http://www.fileshosts.com/DFI/NF4_SLI_D/web/NF4_020.JPG :)

anyway went with 1KW single psu instead so far so good http://www.xtremesystems.org/forums/...ad.php?t=88695


:woot:

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Nice PSU! :slobber: Won't it throw the power out of sync or something if I connect a different PSU to the floppy connector pictured above?

Thanks for the help eva/hell-fire! Although I couldn't fit my second PSU in my case because my dual 120mm radiator was in the way, I decided to just stick the other PSU outside the case and route the wires in from the back. :D

http://img154.imageshack.us/img154/2484/slipsu2ld.jpg

Pretty ghetto looking but at least it works. Wired up my pump, 3 HD's and DVD drive to it for now.

interesting so how ya got the 2x psus configured ?

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Originally Posted by 5150 Joker

Thanks for the help eva/hell-fire! Although I couldn't fit my second PSU in my case because my dual 120mm radiator was in the way, I decided to just stick the other PSU outside the case and route the wires in from the back. :D

http://img154.imageshack.us/img154/2484/slipsu2ld.jpg

Pretty ghetto looking but at least it works. Wired up my pump, 3 HD's and DVD drive to it for now.

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My pleasure bro. Anytime. :)

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Originally Posted by eva2000

interesting so how ya got the 2x psus configured ?

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Looks like the 2nd psu is running the 4-pin aux on the mobo (which turns it on when the system is posted), and it is also running the pumps/fans/drives..? Cant quite tell from the pic, but there are 2 wire groupings coming in. So I am assuming it is powering the peripherals and what not, and the main psu is powering the mobo and vid card.

Stephen if your still around did dual 510's blow your cards up or what, I need to know if you had any luck with this.

My tuppence is that if a PSU has multiple 12V rails, which will all be at slightly different levels...11.8 12.1, 12.0 for example, then connecting a 2nd PSU with a common ground should be fine, as it`ll also have rails that fluctuate slightly around the same level.

Fair enough..the GPU is taking power from the PCI-E slot (one rail) and more power from the PCI-E plug (a different rail) so even with 1 PSU..the 12V rails arent quite the same. I really dont think it`ll matter.

The icing on the cake...the new GPU PSUs from companies like FSP and ThermalTake...they`re just connected to the green and black wires of the main PSU, to boot at the same time and have a common ground.

K

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Originally Posted by G H Z

Stephen if your still around did dual 510's blow your cards up or what, I need to know if you had any luck with this.

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I'd avoid it. It killed one of my AOpens. Two PSU's means two grounds=bad.

Thats exactly what I'm thinking, I just wanted to hear if he had any luck with it. I talked to someone over at PC Power & Cooling and they said don't do it.

Stephen and I both switched to Zippies shortly thereafter, and you should follow suit. :D

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Originally Posted by Gautam

I'd avoid it. It killed one of my AOpens. Two PSU's means two grounds=bad.

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Did you not connect your grounds?

I thought 2 PSUs connected properly would work fine, and because of the GPU power supplies out now, that adds weight to "my" arguement.