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sirplayalot
12-25-05, 10:34 PM
I just got an error message while playing NFS:MU that there isnt enough power going to my 6800 Ultra! I would think 500W is enough! I guess i need a new PSU... :(

Any recomendations?

Medion
12-25-05, 10:46 PM
Assuming you have exactly what's in your sig...

A common misconception on PSU is that more WATTS = better. That is not always the case.

With the newer ATX standard, you need more juice on the 12V rail(s). Newer PSUs actually have multiple 12V rails.

nVidia recommends a BARE MINIMUM of 12V@26A for a 6800Ultra, and that's only if you're not overclocking.

Going by the specs on yours, you have 12V@34A, which should be sufficient (this is actually near SLI certified spec). However, if you're OCing the video card AND the CPU, you're probably breaking this barrier.

If you were to get a better PSU with the same specs, you'd probably be ok. The review I managed to find for your PSU were favorable, but your PSU just isn't as efficient as some better brands, like SeaSonic, Antec, OCZ, or PC P&G.

I'd highly recommend a dual or even triple 12V Rail PSU from one of the above brands, 480W or better for your system.

sirplayalot
12-25-05, 10:59 PM
Well i went inside of my PC and decided to plug the 2 6800 Ultra plugs into 2 different cords (Not 1 splitting cord) and it seems to be working fine at default factory OC (425,1100).

How is the X-Infinity 600W or Antec TruPower 480W?

Medion
12-25-05, 11:10 PM
How is the X-Infinity 600W or Antec TruPower 480W?

I don't know much about the X-Infinity. To be honest, for your setup I'd highly recommend any of the following (from top to bottom):

-PC Power & Cooling 510 SLI - $219.99 (http://www.newegg.com/Product/Product.asp?Item=N82E16817703001)

Absolutely the best PSU you can buy for any gaming system, and it's SLI ready. Keep it for your next system :)

-SeaSonic S12-600 - $159.00 (http://www.newegg.com/Product/Product.asp?Item=N82E16817151025)

This PSU is more than adequate for your current system (12V@36A split on 2 rails), and like the PC P&G, will last you through your next system as well. These things are also surprisingly quiet.

-Antec NeoPower NeoHE 550 - $118 (http://www.newegg.com/Product/Product.asp?Item=N82E16817103941)

Almost as good as the SeaSonic, just not as quiet nor quite as efficient. Still, a solid choice if you need to save some cash.

-Antec TruePower 2.0 550 - $99.99 (http://www.newegg.com/Product/Product.asp?Item=N82E16817103932)

I know I said a 480W minimum, but I really wouldn't go lower than this with your system. The 6800Ultra is a notorious power drain, and yours is factory overclocked. Heck, I've heard that the 7800GTX drains less power than the 6800Ultra.

This PSU isn't as efficient as the NeoHE, but it's still much better than what you've got, and will get the job done.
---------------------------------

As you can see, not all PSUs are created equal. Never go by just the wattage. The best PSU in this recommendation is listed as 510W (but that's because PC P&C lists the sustained amount, not the peak, which is over 650W on that thing).

I'm sure you didn't want to hear that you'd *probably* have to spend at least $100, but it's your PSU, and it's the most important part of your system. You can probably get by with a Truepower 480, but you do so at your own risk.

sirplayalot
12-25-05, 11:17 PM
Thanks a lot man! Im going to stick with this PSU for now to see if it gives me the error and underclocks my card again. Ill keep those PSU's bookmarked!

john19055
12-26-05, 02:42 AM
What happen to the OCZ PowerStream I thought it would be in that list since they make real good powersupplies or least they used to My 470watt is still going strong with it's 33amps on the 12v line.

jAkUp
12-26-05, 02:52 AM
Yes the Powerstream's are very good as well, the Modstreams... are... well, not so good :)

MustangSVT
12-26-05, 05:27 AM
I somehow find it hard to believe that your PSU isn't enough (original poster). Either Ultra X-Connect is lying about their ratings and the PSU ain't all that, or something's going on.

For example, I run an overclocked Athlon XP which does use quite a bit of wattage, 2 sticks of 512mb just like you, and a 6800gt at 400/1100. I also have an audigy 2 zs, 2 hdd's, 2 cd/dvd drivers, and some led fans and yea. Anyway, my PSU is a 431W Enermax that's like almost 4 years old now.

Let's say that your CPU draws more power, but I've run my 6800gt at 430/1200 before very stable and my PSU is only 20A on the +12v and it never had problems. It's never had problems at what I run it (400/1100), and apparently you've got over 30A, or 26A as somebody else in this thread.

Salamandar
12-26-05, 06:44 AM
Power supplies are over rated !

(mikec)

Lemur.fi
12-26-05, 07:25 AM
It is all about selling Wattage.

A decent ~400W PSU would be more than enough unless there is a lot extra junk in the case.

Medion
12-26-05, 10:10 AM
What happen to the OCZ PowerStream I thought it would be in that list since they make real good powersupplies or least they used to My 470watt is still going strong with it's 33amps on the 12v line.


I didn't see it at Newegg, or I definitely would have mentioned it. Those things are amazing.

Either Ultra X-Connect is lying about their ratings and the PSU ain't all that, or something's going on.

Something is going on, and I suspect that his PSU is dying. It worked fine up until recently.

It is all about selling Wattage.

A decent ~400W PSU would be more than enough unless there is a lot extra junk in the case.

Wrong and wrong. Wattage is not the main thing to look for, and I can't think of a 400W PSU off the top of my head that carries enough on the 12V rail for his GPU. Most I've seen is 12V@25A on a 400W PSU, and a 6800Ultra requires a minimum of 26A if it's not overclocked.

sirplayalot
12-26-05, 11:22 AM
Maybe i should have posted the other stuff inside my PC.

I got a 200GB primary HD (Windows HD) and 2 300GB raided together (backup). I got a DVDRW\CDRW drive and 6 case fans. The video card has been working fine since i switched over the cables inside my PC.

Salamandar
12-26-05, 11:44 AM
Your Graphics card should be connected using a power cable that is connected to nothing else !!

Marvel_us
12-26-05, 11:49 AM
I got one of these on way, should be here today or tomorrow.
http://www.newegg.com/Product/Product.asp?Item=N82E16817159056

Just throwing another option out there.

HeavyH20
12-26-05, 12:07 PM
Multiple power rails actuallly, at times, make matters worse. I have seen a number of people load up one rail and barely touch the other. So, in essence, they have reduced their 34 amp 12 V capable PSU to a 17 amp 12 V net. Moving around the items from cable to cable to adjust load avoiding bridging the rails can help.

One note. If you connect a PCI-e device with an adapter to two molexes on two different 12 V rails, the PSU may see this as a short and refuce to turn on. I have seen that more than a few times. On the AGP versions that make use of two separate molex connectors, this problem does not occur.

And, the 550 Watt PSU originally used is more than enough. I am using a 520 watt OCZ (peaks to over 600) to power a 7800 GTX 512 MB SLI system with no issues. I also use a power meter to watch load, and it never exceeds 420 watts, so load is well in hand.

snowmanwithahat
12-27-05, 12:10 AM
hey, i've heard that sometimes the molex connector will go bad, happened toa f riend of mine, just use a diff. molex connector and see if it helps

Lemur.fi
12-27-05, 06:04 AM
Wrong and wrong. Wattage is not the main thing to look for, and I can't think of a 400W PSU off the top of my head that carries enough on the 12V rail for his GPU. Most I've seen is 12V@25A on a 400W PSU, and a 6800Ultra requires a minimum of 26A if it's not overclocked.

I said selling ... and I'm not buying. You seem to be though.

For example Antec Truepower 2.0 380W has 16A+16A* rails for 12V. That is already more than 26A and it is below 400W PSU. Dedicate one rail to the card and use the other for the rest of the system and it works more than fine.

By the way, your suggested Antec 550W has 19A+19A** rails for 12V. Not much difference there.

* Two rails with output of 16A each for the 12V. That is 32A total with certain limitations.
** Same but with 19A+19A = 38A rails for 12V.

bigjohns97
12-27-05, 09:29 AM
http://www.jscustompcs.com/power_supply/Power_Supply_Calculator.php?cmd=AMD

try this out