PSU for future SLI

[stnicralisk]

I have been reading some PSU reviews including anandtechs debunking PSU myths article and I am more than a little confused. Some of the information on the boards seems contradictory to the articles on the front page.

I plan to get a single 260gtx soon with plans to add a second one in the future.

Reading the multi vs single rail the suggestion is given that you simply insure certification and proper connectors are available.

The absolute cheapest PSU with 4x6 pins is around 90$ with many over 150$

If I understand what you are saying correctly it would seem that I could be better off getting a PC&C single rail with good amps instead - then I can use 2 molex to 1x6 adaptors and still not overload the PSU 12v rail in amps.

Is this correct thinking?

I was also wondering about hooking up each card with 1 x6pin and 1 adapted 6 pin if i used a 3 12v rail psu.

Suggestions?

 

[Zepper]

The reason for the 6-pin card connectors is to spread the current load across extra wires so when you connect an adapter to a drive-power Molex, you're putting the load all back on one yellow wire from the PSU and one connector point - not really a good idea unless you know that the card load won't overstress one connector. If you decide to do that anyway, limit the adapters to one per pigtail from the PSU.

.bh.

 

[stnicralisk]

Thanks Zepper, it seems like the suggestion then is to use the intended adaptor for the connections which of course is obvious. The question becomes what power supply to actually get.

I suppose I need 4x6pin connectors (can an 8 pin be split into to 6 pins? 150w to 2x75w) although actually for real future upgradeablility 6x6pin would give me the option for 3way sli..

I am looking at PSUs in the 700w range.

Potential build 4gb of 2.0v ram, e7300, 1x 360gb hd (perhaps a second one later for raid), 1 optical drive, 1 260gtx (with plans to add one later, and perhaps even later a third.)

What PSU in this range would you all recommend? None of them have 6x6pin for under 200 bucks does this mean 3x 260gtx is a poor idea for me? after all if i have to spend 90$ more on a psu for the purpose of the proper connectors i may as well just get a 280 for now and a second one later.

PSU is so confusing.

I believe my current Fortron took a dump on me and killed one of my ram slots and now my current build is unstable.

 

[HOOfan 1]

If you want to spend $750 on 3 GTX 260s then I don't think it is much to ask to spend $200 on a PSU to power them. The Silversonte Olympia 1000W with 6x6pin connectors is on sale at newegg for $199

If you only want 4x6pin connectors, there are plenty of units taht would do for dual GTX 260 for under $150 which again, I don't see as an unreasonable price for trying to run $500 worth of graphics cards.

PC P&C Silencer 750
Corsair TX750
BFG LS680
Silverstone Strider 700W
Silverstone Olympia 700W
and so on and so on.

 

[stnicralisk]

I don't think you understand.

When I purchased my current card the 8800gts it was over 220$, now they can be had for 75 - 100$. I do not plan on spending 750$ on graphics cards. I plan on spending 400$.

200 now for one 200 later for two.

 

[HOOfan 1]

The point still stands....if you are expecting to get a PSU that can run GTX 260 SLI for under $90...you are just going to wind up dissapointed.

If you expect to get a PSU that can run 3 GTX 260 for under $100...then you are just plain crazy.

You could luck out into some deal like the BFG ES800 with a huge rebate and a promo code at newegg...but don't expect a 6X6pin unit for that cheap...you will have to use adapters.

The price of the graphics card may drop dramatically, but the power draw will not, don't try to cheap out on your power supply, especially if you expect it to run multiple GPUs.

 

[theAnimal]

Why not just add an 8800GTS now?

 

[stnicralisk]

The problem is that i have the 8800 gts 640mb.

There are three issues with sli on this card.

Firstly the card is slower than the 8800gt 512 g92 by at least 10% more in some applications.

Secondly it is difficult to find any 8800gts 640s at the moment (only the refresh is available so id have to hunt fs/ft and its not worth it for 8800gts sli imo)

Third I plan to replace the motherboard on this build and give it to my wife so she can play sims and some other games as well as use it for a media pc.

 

[cusideabelincoln]

Running three GTX260s with an E7300 is... counter-productive. But you'd probably upgrade that at some point, because it will hold you back even with just two GTX260s.

Now the performance jump from two to three video cards is even less than from one to two. It is not really a smart move to buy one card now with plans to add another later, unless you plan to do so in the near future. As you put it, your video card's current worth is like $80, yet a single GTX260 or HD4870 will give you the same performance as two of them in SLI. And you also note that it is hard to find your 8800GTS. Well, it may in fact be hard to find a the correct model GTX260 in the future for SLI purposes, let alone find one in the future for a reasonable price. So having a plan to add a third card later is even less smart, especially given the power requirements for such a setup, as new video cards will come out to put yours to shame

 

[yh125d]

A single GTX260 would be borderline bottlenecked by a e7300, depending on the game

 

[Zap]

Originally posted by: stnicralisk
Reading the multi vs single rail the suggestion is given that you simply insure certification and proper connectors are available.

Multiple rails versus single rails... THERE IS NO ISSUE. Really, a PSU being designed properly, being of good quality and having enough power to run what you intend is all that you need. Whether it is on one rail or fifty rails does not matter.

If money is an issue, I'd say just target enough power to run two GTX 260. Even if you can get two of them for $200 used in a few years, by then there will be something you can buy for $200 that would be almost as fast as all three of the GTX 260 while drawing less power.

 

[stnicralisk]

Originally posted by: yh125d
A single GTX260 would be borderline bottlenecked by a e7300, depending on the game

We are getting a bit off topic here but I don't really believe this to be the case. I currently have an e6300 and when it is overclocked to 3ghz I get near the same frame rates as benchmarks get using much more expensive processors with the same graphics cards.

The biggest thing about going with more powerful graphics cards instead of with better processing power is that you have to appreciate the beauty of AA and AF. The higher the graphics intensive settings the less impact a processor has.

As far as game performance quad core currently doesn't have much impact on gaming. In left4dead I have to turn off multiprocessing with just 2. Very few games currently take real advantage of multiple cores even though it is becoming the main stream very quickly.
Because of this the only worthwhile jump over the e7300 is the core i7 - this increases my budget significantly - about 180$ more for the processor and 150$ more for the motherboard.

Honestly I am hoping to capitalize on the new processor by buying the older one for cheaper. I can always overclock the wolfsdale to run at faster rate.

Originally posted by: cusideabelincoln
Running three GTX260s with an E7300 is... counter-productive. But you'd probably upgrade that at some point, because it will hold you back even with just two GTX260s.

Now the performance jump from two to three video cards is even less than from one to two. It is not really a smart move to buy one card now with plans to add another later, unless you plan to do so in the near future. As you put it, your video card's current worth is like $80, yet a single GTX260 or HD4870 will give you the same performance as two of them in SLI. And you also note that it is hard to find your 8800GTS. Well, it may in fact be hard to find a the correct model GTX260 in the future for SLI purposes, let alone find one in the future for a reasonable price. So having a plan to add a third card later is even less smart, especially given the power requirements for such a setup, as new video cards will come out to put yours to shame

Well currently 8800gt SLI benchmarks around the same as a 280gtx.

(i know its toms, trust me i know but.. quickest benches i can find other benches show similar results)
http://www.tomshardware.co.uk/...f-Duty-4-v1-6,746.html
http://www.driverheaven.net/re...%20review/oblivion.php

I know what you are saying has some merit to it. The issue at stake here is that I would like to build a second computer soon and at this point in time I couldn't justify purchasing 2 260's. The 280 is a bit pricey at this moment as well.

The third 260 would likely only happen if it fell into my lap or if someone in fs ft decided to sell their sli setup for a reasonable price. Looking at 3way sli benchmarks I have to admit that I was impressed with how well it had scaled.

 

[yh125d]

Well, I know that my e7200, even when clocked to 3.5gHz, was the bottleneck in both WoW and CoD WaW, not my GTX260. At 19x10 and lower resolutions, at 16xAA and all that stuff, and at lower settings. Like I said, it will depend on the game.


I think an e8x00 would be a worthwhile step up from e7400, and the quads definitely would. the 7x00's are really choked on cache, and doubling the cache alone can make a very noticable difference in games. Add to that how the 8x00 chips overclock a lot better than the 7x00 chips, and it's definitely worth it, imo. There is a lot of performance to be gained over the top of the e7400 before you hit i7 territory

 

[stnicralisk]

So you are saying with an e7200 if you upgraded from a gtx260 -> gtx280 you wouldn't get more frames?

Because if the processor is your bottleneck then you shouldn't be able to edge out more frames with just GPU power.
http://www.tomshardware.com/re...m3-phenom,2148-10.html

This article demonstrates my meaning fairly well.

As you can see COD WAW had some headroom at 19x12 4x/8x
but at 25x16 all the processors were very close - within 5 fps. The same effect could be achieved by turning up other settings 8x/16x for example will close the gap on your bottleneck and another processor.

In farcry processor made almost NO impact at all - unless you had a stock 920 which would bottleneck you here. Again once overclocked I think it makes no difference.
http://www.tomshardware.com/re...am3-phenom,2148-9.html

I would like to see a nonneglible difference between e7300 and e8300 to justify 40$. 2 - 3 frames isn't worth 40$ to me. I will put the e7300 up to around 3 - 3.3 ghz and call it a day.
To justify it for me I would say I need at least a 20 frame difference and I don't mean at 10x12. I play at 1920x1200.

I just think it is better to put the 40$ into my graphics card or into my stomach, but maybe I am wrong I await a reply to show me my error.

 

[theAnimal]

Originally posted by: stnicralisk
The problem is that i have the 8800 gts 640mb.

There are three issues with sli on this card.

Firstly the card is slower than the 8800gt 512 g92 by at least 10% more in some applications.

Secondly it is difficult to find any 8800gts 640s at the moment (only the refresh is available so id have to hunt fs/ft and its not worth it for 8800gts sli imo)

I'm betting the same thing will happen in a few years. It will be hard to find another card for SLI, and there will be a newer, better card.

So my advice is to get a good quality 500-600W PSU and upgrade your video card periodically.

 

[stnicralisk]

Yea I think that is pretty much the consensus. I think I would still like to maintain the option to upgrade to SLI but I have heard some negative things about the nforce boards. I can get another 8800gts 640. I know someone with one but I would have to buy him a card to trade AND buy another card for this current build that I want to place in the living room which would end up costing me 200$ - the same price as just grabbing a 260 gtx.

Thanks for all the input and opinions everyone.

I was given an Earthwatts 650. I know the series is older now how does the 650 compare to the other models. In anands review the EW wasn't very efficient and was kind of loud - this one claims to be 80 plus

 

[HOOfan 1]

The Earthwatts 650W is not even a year old.

Review

 

[stnicralisk]

Thanks hoofan I searched but only found reviews of some older models.

Edit: also enjoying the site itself interesting review of the phenom ii - quite different results compared to guru3d who compared the phenom ii to the i7 920.

 

[cusideabelincoln]

3-way SLI needs tremendous CPU power to see its full benefits. And I'm not talking about upgrading to a faster dual core, like an overclocked E8400, but stepping up to a quad core like the Q9650 or Core i7 920.

Just take a look. Bottlenecks are not mutually exclusive: http://www.guru3d.com/article/...e-performance-review/9

As you can see, adding a third card on the E8400 setup does increase framerates. However, framerates increase even more on the i7 setup. Clearly the Core 2 Duo can be a bottleneck for resolutions 19x12 and below. I should also note that in those particular benchmarks, the 680i platform they are using may in fact the bottleneck. But the point is, the X58 and Core i7 platform do provide tangible benefits for multi-GPU setups, especially in multithreaded games like Far Cry 2.

Also, while I can't re-find the benchmarks, a single strong GPU will give you better minimum framerates than two weaker, last generation GPUs. So a GTX260 would probably give you a better gaming experience than a 9800GX2 or two 8800GTs.