Dual pcie

[ack ack]

been researching ps units, and i've come across units like the Enermax EG701AX-VE 600w that have two 6 pin pcie power connectors, as compared to others like the OCZ 520/600w Powerstream and the Antec Neopower only that have only one. Is it necessarily more efficient to have two pcie connections instead of one dedicated connection and one adapted pcie? would an adapted pcie connection effect a dual rail any different, or do you just lose two 4pin molex? thanks for any replies.

[Chapel]

Adaptors would not affect the preformace of a card. The one thing to be aware of would be hooking up too many devices to one adapator, 2 is usually safe. Also you can get Y-adaptors, which would make 2 PCI-E from one molox.
As for why one PS has 6 and the other only has 1, i couldnt answer. I would assume that the PS you happend to be looking at was brand new, possibly being compared to an older device.

[Frakk]

he said it has two, 6 pin connectors, not 6 if Im right. the performance of the card wont be affected if your voltages stay within the tolerable limit(+- 5-10%). I'd also make sure if the psu has enough current on the line you hook it up with possibly more devices

[ack ack]

ultimately, I'd like to support this configuration:

2 6800 GTs
4 SATA HDs
1 DVD-RW Optical
2-3 120mm fans
Zalman 7700 HSF

this alone without a high end cpu totals to about 480w. would the dual pcie on its own rail be more power effiecient in a rig like this?

[mashie]

ultimately, I'd like to support this configuration:

2 6800 GTs
4 SATA HDs
1 DVD-RW Optical
2-3 120mm fans
Zalman 7700 HSF

this alone without a high end cpu totals to about 480w. would the dual pcie on its own rail be more power effiecient in a rig like this?
Out of curiosity, where di dyou get the figure 480W from? Just wondering since five SATA HDs are around 60W, 3 fans and HSF would be under 15W unless you want some mega noisy/powerful ones. The DVD is at the most 20-25W. That gives you a grand total of under 100W for the perpherials. You will not need 380W just to power two 6800GT.

How do I know? Well on a 240W PSU I have the following running:

A64 3400+
6800GT OC
SATA HDD
18W pump
12W fan
15W worth of lights

And this did still permit me to OC both the CPU and the GPU.

[ack ack]

made my statement based on this calculator. recommended post on anandtech.

http://www.extreme.outervision.com/index.jsp

dunno, maybe its hyped a bit.

[A Guy Named Joe]

ack ack, I would recommend the PC&C 510 PSU or something at least higher. At the minimum, go with the Antec NeoPower 480. The reasoning for this is that as you add more to your computer, you're going to draw more power. The thing is, people don't want to spend over 100 bucks or more on a PSU because they think they don't need to spend that much, but you actually do. Sure the Mobo is the guts of the PC, but the more you add on, the more power you need AND you'll want a PSU that you won't have to buy again in a year or two because you didn't plan for future expansion or new tech that may draw more power.
You best best is to buy with the knowledge your going to use that power in the future. If you don't then no worries because you may someday but if not, at least you know that you won't run into any power constraints in the future.

Just my .02 cents...

[K3LO]

ythe turbocool is a good choice, but it's pretty expensive.

[Frakk]

it is a good choice with a high pricetag. Neopower is also a good choice with a fairly high pricetag. I saw Sky selling one in the trading section for $70. Hell thats a very good price for that psu. If id be looking for one I wouldnt even think so don't let it go:) (u welcome Sky :)) I have the OCZ Powerstream, a very nice psu for an affordable price. wont regret it either.

[ack ack]

ythe turbocool is a good choice, but it's pretty expensive.

I'll prolly save a purchase like the 510 Sli for an FX dream system I build later. My current build is midrange and I was just looking into stability/scalability.

Currently, I have an 500w Ultra X-Connect which haven't gotten the greatest ratings in terms of rail stability and load performance. I must admit, I bought it cos it looked pretty, all shiny and blue, and the modular design was tempting, 'till I saw how huge the connectors were. Don't think I'll run two 6800's on it, but I think it will hold up for the time being. Replacing it with that neopower could be an option tho, that's a sweet deal.

I like the setup and efficiency of the enermax 701ax-ve overall, rumored also that it runs a bit quieter than a turbo cool. can get it at reasonable price too.

[_drunk_]

Well, I have that PS (and from the description, probably even the exact same model), and I have never had any problems. The actual plugs are pretty big, but they aren't that bad.

[A Guy Named Joe]

While it may be true that the PCP&P 510 is pricey, it also holds it's weight. And other units that are advertised better than this, including the Antec models, lose power dramtically as heat rises. But not the PCP&P 510. Check out their website if ya don't believe me.
Also, MaximumPC rated the PCP&P 510 as GUARANTEED to handle the power requirements of a Dual SLI rig, while the NeoPower while a great PSU, was not.
I think the NeoPower can handle dual 6800 GT's, however, the newer X800t cards? No way.
I'm saying it's WORTH the extra money to get the PCP&P 510.

It's only drawback it's a tad loud with the fan, but tolerable. It's your money, but if you plan on upgrading dual PCI cards that draw more wattage, the NeoPower may not handle it if those cards have a higher amperage rating.

[Frakk]

I think the NeoPower can handle dual 6800 GT's, however, the newer X800t cards? No way.


The ATI cards require far less power than nVidia's, especially the 6800 series. even a single 6800 GT (around 120W) needs more power than ANY x800 or even x850(110W at most), and you are talking about dual 6800 gt's(250W?). Lets think about it again :)

[ack ack]

I didn't think the rails on the neopower could handle much above dual 6600gt's anyways. even tho the neopower is a fairly efficient psu its dual rails are weak on amperage, and dual 6800gt's would clearly stress its capacity, especially with a multi-hd configuration attached.

silent pc review tested the both the enermax 701;

http://www.silentpcreview.com/article221-page3.html

and the neopower:

http://www.silentpcreview.com/article177-page4.html

[Frakk]

i assure you that the neopower will handle all you can throw at it.
maximum power consumtion:
dual 6800 gt - 250W
any 64bit or P4 processor - 100W
2x512ddr memory - 20W
6 drives (hd and optical) - 100W
6 case fans - 5W
3 cold cathodes - 2W
the rest: 5W

adds up to around 480W when ALL of your components are running at 100% load at the same time, which not possible. also the psu's peak power output is about 100W more and it will not crash under load. but hey, what do i know? :)

[ack ack]

so basically aim for a decent brand of psu that supports 480w or above, dual pcie is an SLi gimmick, and the stability of dual rail 12v remains debatable.

does that kinda sum things up? or am I way off base?

[Frakk]

i dont know what you mean by dual rail 12V, there are 3 rails, 3.3V, 5V and 12V. each rail can supply a certain amount of amperes, so it doesnt really matter where you plug it in, it is paralell and the voltages wont be affected by that. if you meant dual pcie connectors, then yes it is nice if the psu has 2, but im sure you can get adapters too. I think a stable 480W psu is plenty and there should be no problems whatsoever.

[ack ack]

in some psu's with the atx1.3 or 2.0 spec the 12v rail is split into two dedicated rails, a 12v1 and a 12v2, as in the case of the neopower which supports 18amps on the 12v1 and 16amps on the 12v2. I guess the concept was to separate dedicated components, like the mobo, cpu, ram, from ones with variable consumption, like optical drives and video cards, in an effort to increase stability.