Best Power Supply for Nvidia SLI?

[mongycore]

I've been reading the usual suspects of hardware sites regarding the upcoming release of the new Nforce 4 motherboards featuring the ability to use SLI. From what I've read I haven't been able to clarify if I'd need to upgrade/abandon my present PSU when I switch over.

I have a PC Power & Cooling 510 Deluxe (not the recently released PCI Express edition) and am curious if I have to ditch this rather expensive part of my computer in the near future.

Reading some sites first impressions of the Asus A8N SLI confuse me...in that there's an EZ Plug that should deliver reliable power to the two SLI'd nvidia cards; does that mean I won't have to have two/four leads plugged directly into the cards as you presently do with say the 6800 Ultra's?

Excuse me if these questions seem idiotic; but I'd just like to know if any of you highly informed cats know the answer to this particular question: do I get to keep my PSU for the long haul?

[Gizmo]

I don't believe it is currently necessary to plug an additional power lead into any of the video cards on the market today for PCI Express, because the bus power connectors were designed to provide additional power over the AGP and PCI specs (but I could be wrong). Even if it is, I would suspect that the cards will accept a standard power connector from the PSU. As far as EZ Plug, I was under the impression that existed to provide power to the CPU for situations where the PSU doesn't have the ATX-12V connector.

In any case, I believe your real question needs to be whether or not the PSU can handle the load, because I've not read anything to lead me to believe that PCI Express video cards have an unusual connector for power.

[Áedán]

PCI Express can deliver 75W of power. We are already at the limits of that for those who wish to overclock/mod their graphics cards heavily. Standard molex still seems to be the order of the day for additional power to graphics cards.

[cadaveca]

pci-e cards use a 6-way power connector, for the x800's anyway. included with most packages is a molex branch-connector so you get the 6-way connector.

The connector featured on the asus board provides extra power to the pci-e lanes while in SLI mode, as some cards will require the additional power. here's a pic of 2 6800 ultras with the sli-connector in place. you can see the 6-way pci-e power connectors(black). with the ultra's, it seems almost impossible to get sli working right without the easyplug powered, and some have been able to get the cards running without the pci-e power connectors, but i've seen the nvidia bios lower the clocks on the cards when they do not have sufficient power. I personally would rather have each piece on it's own power connector, and make sure that my motherboard was not being pushed to hard, or the cards either.

i recommenda 600w PSU or higher fr an ultra SLI rig.

[danrok]

This question is purely academic right now. AGP 6800 Ultras are very thin on the ground. PCI-e 6800 Ultras are as rare as rocking horse poo.

[cloasters]

Is this a step backward, or what? I hoped that the need for SLI went out with the dinosaurs. I't's always something.

[Daniel ~]

I suspect it won't last long, way to expensive, not to mention awkward for most users....

[mookydooky]

Originally Posted by Daniel ~

I suspect it won't last long, way to expensive, not to mention awkward for most users....

Actually, it could work out. I saw some benchies and an SLI setup with dual 6600GTs will outperform an X800 in many tests. The dual 6600GTs are cheaper than a single X800.

[Gizmo]

I'm waiting for the Son of Voodoo 5. You know, a video card with like 8 graphics cores on it.

[cadaveca]

Originally Posted by mookydooky

Actually, it could work out. I saw some benchies and an SLI setup with dual 6600GTs will outperform an X800 in many tests. The dual 6600GTs are cheaper than a single X800.

just wait until both cards get 16 pci-e lanes, and the cards can use them. Graphics quality so good you can almost not tell the difference from reality is pretty darn close!
From what i've have seen floating around, Via is ahead of the game, as they had already got the north/southbrodge pci-e link working ok, so 64 lanes is quite possible, but not under BTX standards. who knows what will happen. Next big jump is multicore, and the PlayStation3 has mentioned "cell-processing"(8-16 slower cpu's omni-directionally linked) for a while...
Nvidia and Sony have a deal that may see dual gpu's in the PlayStation3.......

January 31st for the big ATI price drop. Don't forget that there was some insider trading lawsuits in the works....

[danrok]

Originally Posted by cloasters

Is this a step backward, or what? I hoped that the need for SLI went out with the dinosaurs. I't's always something.

It's more of a desire than a need.

[Daniel ~]

Originally Posted by mookydooky

Actually, it could work out. I saw some benchies and an SLI setup with dual 6600GTs will outperform an X800 in many tests. The dual 6600GTs are cheaper than a single X800.

I liked the dual Voodoo's, but they took up 3 slots minimum to get good cooling. I'd be surprised indeed if SLI were to able to hold their current price positioning,(Twice the hardware) But hey been wrong before. You can do a lot when you can control the price of an entire line of cards.

Can any two 6800Gt's be used in SLI or do have to buy a pair?

[danrok]

They need to be exactly the same make and model and have the SLI connector on them.

[Gizmo]

I would expect that they have to be the same configuration, e.g. same gpu core, same amount of memory, and probably the same firmware revision. But it's not like you have to buy matched cards (like you do with dual channel RAM).

[cadaveca]

It's kinda finicky, it seems. Sometimes the cards MUST BE the same manufacturer even, sometimes not. Makes me think it's the bios that makes the difference...only a few manufacturer's deviate from the norm.

All pci-e 6xxx nvidia cards should feature an SLi connector, to my knowledge. Pretty sure it's part of Nvidia's requirements.

[danrok]

None of these PCI-e cards appear to be SLI cards:
http://www.overclockers.co.uk/acatalog/6600.html

I've only read that the cards must be exactly the same, but the proof is always in the pudding! We'll find out soon enough!

[Gizmo]

You're right, Danrok. The SLI connector is conspicuous in its absence. Hmm.....

[cadaveca]

There is good reason for it being missing....especially when you think about vidcard manufacturer's having to ahve 2 PCB's for one level of card...you'd think that they'd only have one to cut down on costs....