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Best x1900xt Crossfire PSU

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Internal

Member
Joined
Dec 7, 2005
Well I'm an idiot.

My buddy buys 3 hdds, 2dvd burners, 4x1gig XMS DDR sticks, 4800+X2 and two x1900xt's and a thermaltake 550W PSU and I don't even tell him that his PSU won't run all of that.

So sure enough, when both 1900xt's kick into 3D mode, it crashes the computer.

What was I thinking?

Anyways I didn't tell him to get that PSU, I just should have known it wasn't gong to work when he showed it to me.

OK so whats the best and whats the best for the $$$?

THX guys
 
personally i would have his current powersupply run the hard drives, optical drives, maybe cpu. and then buy another one to run the grapchis cards and the other stuff.

but his case may not fit 2 powersupplys. and the noise might be a problem
 
for that i would pick up MINIMUM a 520w OCZ powerstream. But he ought' to shell out the money for a PC P&C 510w SLI psu... It don't look like money is really a problem for him lol.
 
First off, I thank everyone for responding.

I agree with rattle as well.

Even if those OCZ's did work, they'd be RIGHT at the very edge of working and thats just asking for trouble. Even if they did work, as soon as I start Overclocking that CPU and GPU's, it going to hit a wall.

I did the PSU calculator and it came back with 600watts of power to run all of the devices that he bought.

So realistically we're going to need a continuous 600W and a peak of 700W.

Now, lets talk about the most important thing: Amperage.

I'm finding non of these dual rail PSU's have enough amps on each rail to run these cards and devices.

So, is that awesome fortron PSU a SINGLE rail PSU cause I'm showing 4 rails @ 15amps a peice. I don't see how that's enough when these cards require 22-25amps @ 12volts under full load.

I'm finding if you want to do what my buddy is doing, you need a single rail PSU.

Crazy stuff I tell you.
 
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Splitting up the rails doesn't matter too much anymore because it seems that that's the way mobo's are being made today. It use to be server mobos doing that and now it is desktops while servers are adding more and more stuff to thier mobo's.

If you gave everything it's own 15amps I can't see what the problem would be. 15amps should be enough for any one thing. I mean I am running some power hungry stuff using a dual rail and it does just fine so I would say run whatever PSU that will power your rig within reasonable means.
 
avalanche83 said:
Splitting up the rails doesn't matter too much anymore because it seems that that's the way mobo's are being made today. It use to be server mobos doing that and now it is desktops while servers are adding more and more stuff to thier mobo's.

If you gave everything it's own 15amps I can't see what the problem would be. 15amps should be enough for any one thing. I mean I am running some power hungry stuff using a dual rail and it does just fine so I would say run whatever PSU that will power your rig within reasonable means.
well, almost anything... ;)

ViperJohn said:
That 811/927 card I posted the picture of earlier had 3D peak input power draws hitting 194 watts with the core dissipating roughly 160-165 watts.

BTW that 194w peak 3D power consumptionis 16.16 amps at 12 volts (and people wonder why they have so much trouble running a pair of em in a CF setup with an split 12v rail ATX2.0 PS lol).

Viper

http://www.ocforums.com/showpost.php?p=4337509&postcount=991
 
stang8118 said:
for that i would pick up MINIMUM a 520w OCZ powerstream. But he ought' to shell out the money for a PC P&C 510w SLI psu... It don't look like money is really a problem for him lol.

The 510 is not enough for X1800CF + intel Presler DC. When we talk X1900CF and an OCed processor, we need 700w PSUs w\ atleast 45a 12v rails. The PC Power & Cooling 850ssi is perfect IMO and I'll be buying one soon enough. FYI I sold my X1800CF because of the 510 not being able to power them when loaded(with [email protected]).
On the otherhand if you do not OC, then the 520 Powerstream or the 510 Turbocool will do.
 
How about the Enermax Liberty 620?

Guys are great btw, not many people in this small world even having this discussion so its nice to get help.
 
zeimbo said:
you want:
pc p&c
ocz powerstream
fortron (fsp)
silverstone
seasonic
or zippy

Most recommendations are for a single rail psu with 38A on the 12V line if running a pentium.

As you are running just an X2 a psu with 32A on a single rail should be fine. I've read reviews where they had all kinds of problems (Xfire and FX60) until they moved to using an OCZ520Powerstream.

That OCZ would be the minimum to aim for. They put a power measuring device on that setup and it was at 412W at load so there's no reason the OCZ couldn't handle the X2 with Xfire.

Next would be the Silverstone ST56ZF (36A) and then all the 1kW units :D

If it was me I'd get the Silverstone due to the higher rating. You won't notice the higher noise from it because of the two vacuum cleaners doing the video.
 
Internal said:
My buddy buys 3 hdds, 2dvd burners, 4x1gig XMS DDR sticks, 4800+X2 and two x1900xt's

Fortron Epsilon 600W or 700W, Zippy PSL-6701P or PSL-6720P(G1), PC P&C 510W, Sparkle FSP550PLG-SLI, Silverstone Zeus ST56ZF.
 
This is with X1800CF @ 700/800 and a Pentium D [email protected](draws 250w) on a PC Power & Cooling 510. @ raptors and 2 80gb SATA, a 18w waterpump, 2 optical drives.
 

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