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PSU for OC x1900xtx and oc 165


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The rails on the GX are not rated for more than 15A per rail.

 

uh

 

my rails are 18A each

 

Im sure that the GX can support x1900s at stock clocks, my enermax liberty can also. It is not as much an issue of can this psu provide me enough watts. More so an issue of very few psus out today can provide high wattage AND a high load of amps on any individual 12V rail. The 520W ocz from the guide looks like it would provide enough, but if I am going to buy a new psu it would make more sense to me to bu something that will last me in the future too ans im not sure how much longer it would be able to do that in cming hardware genereations.

 

well

 

lets see

 

X1900XT and X1900 Crossfire = 625/1450 stock speeds

Pentium D 930 = 3.0Ghz per core, 2MB L2 cache at stock speeds

 

 

X1900XT and X1900 Crossfire = 625/1450 stock speeds

X2 4400+ = 2.2Ghz per core, 1MB L2 cache at stock speeds

 

 

X1900XT and X1900 Crossfire Master = 625/1450 stock speeds

3200+ Venice = 2Ghz 512k L2 stock speed

 

 

you with me so far?

 

 

all of these psu's will power this setup:

 

OCZ 520w Powerstream

OCZ 700w GX

Enermax 600w Whisper

Skyhawk 570w modular

 

 

the only psu that will NOT power full Crossfire mode so far is the OCZ 600w Powerstream...something to do with the split rails or something I dunno...it just won't boot the rigs when Crossfire is setup properly and enabled...but it will boot these boards with all the above hardware as long as the Xfire cards are reversed, so Xfire cannot be enabled.

Go figure eh.

 

 

 

ok

 

 

you still with me so far?

 

 

aight

 

 

 

X1900XT + X1900 Crossfire Master @ 689/1570

Pentium D 930 @ 3.85Ghz

 

 

X1900XT + X1900 Crossfire Master @ 681/1550

X2 4400+ @ 2700Mhz

 

 

X1900XT + X1900 Crossfire Master @ 690/1585

3200+ Venice @ 2600Mhz (this cpu will do 2750 but the board won't for some reason lol)

 

 

ya so...still with me?

 

 

ok, here's the list of psu's that work:

 

OCZ 520w Powerstream

OCZ 700w GX

Enermax 600w Whisper

Skyhawk 570w modular

 

 

and again the 600w Powerstream...well...it won't boot at stock speeds so there's no testing it with everything overclocked...

 

 

 

 

 

the point is...the 4 psu's that I have tested so far work stock and overclocked...dual core cpu's stock and overclocked...SATA II RAID 80GB x2...fans....whatever I plug in, they work, and they work great.

 

The 700w GX psu is pretty fantabulous and is quickly becoming my favorite, even over the 520w Powerstream that I have loved forever.

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uh

 

my rails are 18A each

 

all of these psu's will power this setup:

 

OCZ 520w Powerstream

OCZ 700w GX

Enermax 600w Whisper

Skyhawk 570w modular

 

The 700w GX psu is pretty fantabulous and is quickly becoming my favorite, even over the 520w Powerstream that I have loved forever.

 

We need a lesson in how to understand PS rating here lol.

 

On the OCZ 700 (which is a killer PS for the money) you can load each 12V split to 18 amps without going over current setpoint for each split but you can't load all four to 18 amps at the same time. That would be 864 watts.

 

Look on the PS label. The total combined load of the 3.3, 5 and 12 volt rails at same time is 680 watts max. 150 of that 680 is reserved for the 3.3 and 5 volt rails combined. Now if you load the 3.3 and 5 to the 150w combined max that leaves 530 watts (44.16 amps) you can pull off the four 12V splits combined with no individual split to exceed the 18 max.

 

Now the 3.3 rail is little used and the 5 is fairly lightly loaded these days so say you have a real world load of 100 watts them. That leave 580 watts available for 12V loads or 48.33 amps total combined load on all four 12V splits at the same time again with no individual split to exceed 18 amps max.

 

With dual core CPU on an AMD MB and the magic box fully loaded up you will have about 4-6 amps on 12V2 (4/6/8 pin MB aux connector). 12V1 will be carrying about 12-16 amps depending on the CPU, CPU speed and Vcore, the number of drives, GFX cards, etc, etc, etc. 12V3 and 12V4 each carry one PCIe aux connector. They may carry some of the molex and/or SATA connectors to taking them off 12V1 but the PS would have to be opened to and the circuit distribution checked to know for sure (unless OCZ Tony will dish out the goods lol).

 

Now with a stock OC'ed x1900 CF setup and a 2.8 - 3.0Ghz DC CPU ripping along in your favorite blood drenched 1st person shooter you will have about 14amps or so on 12V1 (number of HD's will effect that some), about 6 amps on 12V2, and peak PCIe aux input of about 8 amps on each x1900 for a total of about 36amps peak (432 watts) 12V load. Average load will be lower depending on what the GFX cards are doing at any given moment in time.

 

The OCZ 520w PowerStream (33amp single 12V rail) is not enough PS for a reliable x1900 CrossFire setup BTW. That is the power supply I use to test all my modded cards and I can take it down regularly with x1900CF and 7800-512 SLI pairs. "I wonder why the computer it did that" while you are benchmarking / 3D gaming will be muttered under your breath often using it.

 

No ATX 2.0/2.1 PS (12V1/12V2 split) that follows the specs to the letter will handle a 7800-512/7900 SLI pair or a x1900 CG pair reliably as they will all drive 12V1 well over the 20amp max current limit for the split.

 

Viper

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im sure people will still ask this question - as they are still confused, like i am - is having a 600watt ocz powerstream a safe bet for dual 7900gtx's or for 2 equivelent cards in cross fire

 

The OCZ PowerStream 600 is a split 12V rail (12V1/12V2) PS with a max of 20 amps on 12V1 (12V2 only power the 4/6/8 pin MB aux connector - CPU2) if the PS truely follows the ATX 2.0/2.1 spec). 12V1 one powers damn neare everything that is 12V in your box. A pair of 7800-512's in an SLI or a pair of x1900's in a CF would have no trouble running 12V1 over 20A. While 7900 are not as power hungry they would too.

 

Viper

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would the new OCZ GameXStream 700watt be a better buy ?

 

 

Type ATX12V

Maximum Power 700W

Fans 120mm fan x 1

PFC Active

Main Connector 24-Pin

Dual +12V Yes

SLI Support Yes

Modular Cabling Support No

Over Voltage Protection YES

Input Voltage 100 - 240V

Input Frequency Range 50/60Hz

Input Current 10A @ 115V, 5A @ 230V

Output +3.3@36A,+5V@30A,+12V1@18A,+12V2@18A,+12V3@18A,+12V4@18A,[email protected],[email protected]

 

 

 

1 x 24-pin ATX

1 x 4-pin/8-pin CPU

2 x PCI-Express

6 x 4-pin peripheral

2 x 4-pin floppy

6 x SATA

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would the new OCZ GameXStream 700watt be a better buy ?

 

 

Type ATX12V

Maximum Power 700W

Fans 120mm fan x 1

PFC Active

Main Connector 24-Pin

Dual +12V Yes

SLI Support Yes

Modular Cabling Support No

Over Voltage Protection YES

Input Voltage 100 - 240V

Input Frequency Range 50/60Hz

Input Current 10A @ 115V, 5A @ 230V

Output +3.3@36A,+5V@30A,+12V1@18A,+12V2@18A,+12V3@18A,+12V4@18A,[email protected],[email protected]

 

 

 

1 x 24-pin ATX

1 x 4-pin/8-pin CPU

2 x PCI-Express

6 x 4-pin peripheral

2 x 4-pin floppy

6 x SATA

 

 

Definately. It really gives huge bang for the buck and it has it's butt distributed where it needs to be to get the job done.

 

Viper

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hey all,

 

i am also in this situation. i am getting a DFI LP ultra-D mobo with the following components

 

opteron 165 0610DPMW @ 2700mhz stock volts

x1900xt (will oc eventually)

ocz gold rev2 pc4000 512x2

2 sata2 hdds (250gb + 80gb)

2 dvd drives

SB audigy 2zs

 

but don't know what psu to get. i was thinking of the ocz powerstream 520w since i heard it such a great psu for the ultra-D, but don't know if its quiet. also was thinking of getting a liberty 500w for the modular cables but have been reading that it is a hit or miss with dfi boards. so basically i'm asking for a quiet, near silent psu that can run stable with my parts above. if it happens to be the powerstream 520w then i'll probably spring for the gameXstream 700w. thanks.

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buy the gamexstream. That is what i am going to buy and can tell you from personal experience the 500W liberty will have voltage drops on the 12V line if you plan on doing anything over mild oc'ing. It is the psu I currently have and although it runs everthing stock fine, when I crank up the gpu it cant feed it sufficiently. It and a couple heat issues im dealing with concurrently I feel are what are holding me back from reaching the ceiling of my components on my current cooling. I also bought it because of the modular cables, but that was for my previous pc when I was using a xqpack case and extra wires were a burden. If you have a full size case buy a dremel and you will find all kinds of ways to hide those cables.

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lol, you know igronically i had a Qpack too w/ a liberty 500w in it also LOL. but it was with a 7900GT CO SC, it handled it great, just now i want a desktop computer again so i parted it plus i have a X1900XT now and didn't want to put it in a small case. i will be getting the gamexstream when it comes back into stock at newegg since it is only ~$20 more for it. thanks on your quick responds, now i need a NB fan replacement because i have a accelero X2 to put on my X1900XT and i know it blows the hot air on to the board. is the chipset fan really that loud?

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it can get pretty loud. Im going to be buying one of the evercool replacement heatsinks soon.

 

THe xqpack are some sweet little cases no doubt. I still have mine, im just going to build a download/aim box out of it. Save me some cpu cycles while im raping newsgroups.

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i have a spare vantec vga fan (the copper one with no leds) and was thinking of using that. i would consider the ting jing chipset cooler if i could find a place that has them in stock in the US.

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