Nvidia Power Requirements

[Merovingian]

I know that nvidia recommends 480W of power for a 6800Ultra SLI system. No where on the site does it describe how many amps on each rail. I assume that the power is heavy on the 12V rail which is a concern for me because the system I am building for a friend includes two 6800GT's flashed to ultra and a new overclocked X2 dual core processor AND 12 SATA drives. That's all 12V rail stuff assuming that the video cards are 12V hungry. So I'm planning on running two 550W PSU's inline inside a stacker 1 case but I want to try an estimate if I will have enough power on the 12V rail (45A sustained Max after efficiency losses and 60A Total). Question is, how many amps do each video card require on each rail. Thanks for your help.

 

[Continuity27]

I believe they need about 4 - 5 amps each on a 12V rail.

 

[Gamingphreek]

The Video card will be the least of your worries. 12 HDDS!!! What in the hell are you storing on all of those.

For a job like this i would HIGHLY recommend nothing less than a Zippy or PCP&C. Dual PSU's aren't really worth it.

-Kevin

 

[ddogg]

i think about 5amps on the 12V rail.

 

[Merovingian]

5 amps? Phew! Just enough. Dual PSU's not worth it? I can get two quality 550W PSU's with dedicated circuitry for under $200 with tax and shipping, as opposed to spending $300 on a 700 watt psu that won't even meet my power requirements. I'm open to suggestions and your input is well appreciated, thank you. About the purpose of the media server... The server will be installed by yours truly into a home with media consoles that will play cracked DVD's over a network. The DVD's are property of my client/friend so every thing is legit and the reason for backing up this huge collection is to be able to stream to any TV in the house without having to find the physical DVD. Other reasons contributing to the decision include "lost" or stolen DVD's over time and the ability to have "tivo" like functions (backed up to the server) that can be watched from any TV in the house. We are going with 12x400GB WD drives in raid 5. He wants the machine to be his personal computer, in which case I'm going to get rid of one of the 400GB drives for a raptor drive. Still I think it will be too loud and it belongs in the closet with a litttle OC'd venice chip but he likes to hear the power of his super server, anyway.

 

[jdogg707]

Why in the world do you need SLI 6800GT's for a Media Server? The hard drives I can uderstand to a point, as well as a dual processor (depending on how many people will be accessing the server at once, but there really is no reason to overclock), but that much graphics horsepower is a waste of power, which is something you will need for the 12 400GB hard drives you plan on using. If dual PSU's is something you want to mess with, then more power to you, but I would go with the PC Power and Cooling 850W PSU, which will power that rig with no worries. Drop the SLI, get a quality single PSU solution, and enjoy.

 

[Merovingian]

Good point and I would agree but the problem is that this is not for me and it will be a dual use computer. Please read above post. I don't need but a sempron to serve the data and onboard graphics to use as a media server. He wants to use the computer that serves the data DESPITE what I would consider to be unacceptable noise levels from the HD's. With that in mind, I need a minimum 35A after efficency losses I figure. So with two 550W PSU's with 30A on the 12V rail each makes 60A, right? 60 x .70(70%efficency PSU) equals 42A on the 12V rail, right? So unless your 850W PSU serves up 720W on the 12V rail for less than $200, why would I use that PSU? Just curious.

 

[Gamingphreek]

To crappy 500watt PSU are not worth it. I will garauntee you that the Zippy and PCP&C high end models will supply work MUCH better than the other 2.

Additionally do not attempt to game, and use the computer as a media server, and do a whole mess of other crap on it. Just build a nice gaming system then build a cheap media center PC.

If you are going to put 12 HDD all on the PCI bus you are crazy. MASSIVE bottleneck. YOu seem to have plenty of money. Get a cheap Opteron processor, and a board with PCI-X support. Get a nice PCI-X Raid card for all those HDD's.

Additionally how many DVD's are you backing up. I highly doubt you will need 4.8 Terabytes of space unless you have ~600 DVD's.

-Kevin

 

[RussianSensation]

This guy better must be 75 years old if he is so lazy as to copy ripped-DVDs onto a DVD and put them into a DVD player.

 

[michal1980]

Originally posted by: RussianSensation
This guy better must be 75 years old if he is so lazy as to copy ripped-DVDs onto a DVD and put them into a DVD player.

I think it would be pretty sweet to have 600 dvds at the push of a button, and then keep the orginials somewhere else. might have to actually consider doing that. except not as crazy as this guys setup. but worth considering.

 

[imported_michaelpatrick33]

With those components

I think Gamingphreek pretty much said it. You do not want PCI 32bit 33mghrtz hard-drive controllers if you are going to 12 hard-drives. Of couse going the Opteron route raises the dualcore expense greatly and eliminates overclock potentials more so than the X2. HMMMM

 

[Merovingian]

I'm pushing to put the machine in the closet but if he want's it in the same room to game, he's going to get a raptor drive for the applications. As far as the media bandwidth goes, I will never need more than the 133MB/s to stream to multiple TV's at once and the gigabit network for other files is limited to 125MB/s anyway so going PCI-X is kinda redundant for this purpose.

As for the zippy PSU's, I don't think they have enough power on that rail to power this system, I need 35A on a dedicated 12V rail. So right now I have 60A, at 70% underload brings me to 42A. I need those extra 7A as a buffer to keep the effiency high and the system stable. Show me a single PSU with 60A at a resonable price and I would be open to it.

Dunno how big the DVD collection is but it's big. I don't think it's over 300 but maybe he thinks a blockbuster subscription and netflix subscription will change all that as well as recording HDTV. So in raid 5 he will have a whooping 4.4TB on tap.