Hello,

I don't much about SLI. Long ago when I was tempted to try it they wanted you to use specific slots for 2 card SLI even on motherboards with more than two x16 slots (including my current). Are you limited on what slots you use for 2 card SLI with newer motherboards?

I'd like as much airflow as possible around my video cards so they keep cool. I need at least 2 other PCIe cards on my system. I was thinking of building a new system with an extended case (CM Haf x).

Does anyone know if there are any limitations on the Asus Maximus motherboards for 2 card SLI config?

Which version is that? It's not the Maximus V. In any case, if you look in the manual or even on the board, it should tell you which PCIe slots are PCIe 3.0 x 16, x8, etc.

The one I intend to get is the Maximus VI Extreme. It has 4 or 5 x16 slots.

Thats looks like Asus Maximus VI Extreme Haswell Z87, if its anything like the Ivy Bridge version ASUS Maximus V EXTREME LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 Extended ATX Intel Motherboard, one of its features is that unlike all Z77 boards, it comes with 2x 16xPCIe, check the back (remember the NDA is still on so im not even sure if the Z87 has dual 16x slots as default like X79, but i somewhat doubt it, thinking we will see Ivy Bridge E, so they have to mantain the X79 differentiation),



In theory the first two reds should be the ones to use on that mobo for SLI, not sure if it will work using first n last.

Now this is $400 motherboard, its more meant for heavy overclockers, so my suggestion is to check the hero version, as it will be a little cheaper and has different disposition of the pci e slots that might play better, it probably wont have have twin 16x pcie like X79 board.

Back to the hero version here is a layout of it,



If you want triple slot spacing between your GPUS, you are going to need an Extended ATX motherboard, like EVGA Classifiend, etc. Or drop the LSI card, the Z87 mobos like the ROG series come with 6-10 Intel Sata III (i believe not sure as until the NDA is lifted no one knows for sure), but if it is like that you can probably control 4 pin drives and the 2 ssds via the intel built sata controller, do you use the LSI for raid?

Personally i would suggest against SLI, as it will introduce more heat to the case and increase the temp inside, meaning it will either run hotter or you will need to increase the speed case fans to compensate. Second, even when scaling on SLI is really good, its totally dependant on drivers, so you will have to update constantly, and hope that whatever you play gets supported, this is not a big deal as i also update constantly when im planning on playing games on release with a single gpu, but its a little more complex for sli, sometimes you get extra things like microsuttering etc, this are avoided most of the time on single gpu setups. The only reason that personally will go into SLI is when 4k monitors are release and are sub $2k, as driving 4x 1080 is going to be hard... probably a SLI of whatever is currently available will be good idea for those who enter first the 4k market... but there is a huge reward vs risk, much more pixels =) so im willing to deal with more issues for much better experience, but this is still far, maybe a gen or two of GPUs.

Now if you are entering SLI because you want to, and you want to experience whatever it brings.... then go for it, there is nothing better for me than learning and enjoying this hobby. But this gen, im only going for single GTX780, its going to be 20% faster than GTX680, probably around 40% faster than my GTX580, that should keep me good now than im running 2560x1440, i have no super hard rendering games in the horizon, just Neverwinter, LOL, DOTA2, Diablo3 and SC2 takes my time, none of those are that demanding that will requiere sli.

Remember that having the size of the PCIe doesnt mean its electrically wired on the mobo, you have to look in the back of the mobo to see if they are truly a 16x, now thinking that the X79 is the only one that has from intel twin 16x, the Z77 only has 1 by design, some mobos do come with 2 but at the design of the mobo manufacturer and sometimes uses extra chips to manage it. Until intel lifts the NDA (june 3) we wont know for sure how many 16x pcie it will come with, my guess is still one to keep the X79 desireble for people that truly want twin 16x PCIe 3.0 slots for sli/xfire.

From a sneak peak on Guru3d ASUS Z87 Republic of Gamers Motherboard Series
So its practically like Z77 versions.

My suggestion is wait sometime for haswell bugs to be work out, maybe couple of months will be wise. Also on launch Nvidia probably will only allow reference cards, so wait for to see how good are the GTX780s with custom coolers, and see there what to go for, things that i would start to buy is Case, PSU, ssd/hdds i dont see much changing before august.

Thanks if you deal with raids as much as I do, you know that the onboard solutions suck. LSI is a heavyweight controller with 1GB of cache and a great processor. I may eventually even add SSD cache for the spindle raid. It is like comparing an onboard video to a 680GTX.

As for the reason I want SLI is that I like games like Crysis 3 and want 16x, graphics detail very high and 2560x1600 and I don't want it dropping below 30fps (ever).

I've been looking for an XL-ATX motherboard that I like but there aren't many from which to choose. And on most, even if I were to try triple spacing, I'd come up 1 slot short for all my components. Lastly while I may want triple spacing not all the x16 slots are wired for x16 and I'm not sure how much of a concern that is for SLI but I'd imagine I want the x16 slot to be wired as x16.

I think the primary issue with the first picture would be finding a SLI bridge that long. And unless we talk about very expensive Z87 boards with a PCIe multiplier chip (PLX), none of them will have x16 SLI, simply because the CPU has only 16 PCIe lanes - so the best you can get is x8 + x8. Sure, you can see more PCIe slots there, but that is because usually you get :
1) x16/NC/NC or x8/x8/NC or x8/x4/x4 combinations from the CPU PCIe lanes
2) few extra lanes are coming from the Z87 PCH, usually those are the PCI-E x1 and PCI-E x4 slots.

THanks

I think I can get a 140mm sli cable. They are $17 each from MSI.

I'm very new to SLI so could use lots of facts on it. I just read up on PLX. From what I can tell, it offers basically nothing, x8 sli titan gtx would be faster than x16 PLX SLI - would you say that is correct?

Then, there is the basic question - do you even need more than the bandwidth supplied by PCIe 3.0 x8 at your resolution?

From what I've read on other sites, I should be OK with 8x PCIe 3.0 SLI config. Abula's diagram is very close to the right solution for me. If that motherboard had 1 more slot below the last one it would be perfect! I wish there were more XL-ATX motherboards. I think I'll limp along with a titan when a 2 slot air cooled solution becomes available and wait for a newer 2011 XL-ATX motherboard to come along for haswell-e and get an x99 motherboard.

Thanks everyone for your help.

For Haswell E we are very very far away, for sure more than a year, maybe two. Ivy Bridge E is coming on September (i was hopping they will not release it and just move on to haswell E, but its been confirmed), so you can expect more mobos there for LGA2011, probably XL ATX mobos, but do remember than since you are populating a lot of PCIe slots with soundcard/lsi controller, you probably will make all be 8x or but depending on the mobo it can drop to 8x8x4x4x, forcing you to use the GPU on the first two slots, or a mobo like you were planning Extreme which accoding to what guru3d posted it can run all other PCIe at 8x.

For haswell E minimum will be September of 2014 but broadwell (none E) will be out by then.... and since intel delays their high end so much, my guess is going to be released close to skylate (none E) 2015, at some point i feel intel is going to skip one of the E iterations, but who knows....

For now i dont need a six core cpu nor mulitple gpus, nor i use muitiple PCIe slots, so ill stay with none e versions for some time. Until i see 4k monitors arrive and i venture back into SLI.

You are correct, I should have said the next iteration of x99 chip for LGA 2011 motherboards.

And about the TITAN im still toying with getting one, just i dont like the design of cooler, i wish i could get a DirectCUII with it, but dont seem like its going to happen. So for now im considering either to wait for the GTX780 and wait for custom coolers like the DirectCUII, or get a TITAN and buy a Prolimatech MK-26 Black, although not sure if it will fit on TJ08-E (im not sure it will fit on 4 PCIe slots with the fans), weight its not an issue as the TJ08-E hdd cage has a support for the GPU, but the width of the card worries me, but i have Fractal Design Define R4 on the way to me.... so its getting tempting to try a titan.

It looks like there may be a windforce version of the titan relatively soon as well as an inno3d ichill all in one water solution (arctic cooler). I'd prefer directcu for the quietest possible solution as I could never tolerate the stock NVidia cooler on a titan. When we finally have some Crysis3 benchmarks for the titan vs. the 780 I'll be able to decide which to get depending on bang for the buck.

http://www.youtube.com/watch?v=0jMzHeo6 ... r_embedded
http://wccftech.com/gigabyte-geforce-gt ... tted-wild/
http://wccftech.com/inno3d-unleashes-ic ... d-980-mhz/

Hopefully they are just tied up in a non disclosure agreement about a directcu model.

In case you are instereseted, GTX780s are out, and only seen one review with custom cooler,

Gigabyte GeForce GTX 780 WindForce 3x OC review

Thanks!!!

I do so hope that a DirectCU 780 will be released soon. I don't see the windforce on any sites for sale yet. THe EVGA is but out of stock. However I haven't seen any nice reviews like the one for the windforce with any statistics.
http://www.evga.com/Products/Product.as ... P4-2784-KR

Another review of the Windforce GTX780: http://www.techpowerup.com/reviews/Giga ... TX_780_OC/

Thanks so the interesting thing is the Windforce is a tiny bit louder (1db) a little hotter running and they both get the same score in Crysis 3. (The Windforce might have been better in others, I didn't bother to look).

I might get one of these cards if a DirectCU does not come out soon.

I did just notice this on Asus' web page. I don't know if it is worth waiting for but I probably will wait -
"ASUS will also be showcasing GeForce® GTX 780 DirectCU II graphics cards with a completely redesigned cooler at Computex Taipei 2013"

Waiting is relatively easy to do since I can't order the windforce or the acx version of this card yet

Computex...... June 4th to June 8th... another couple of weeks to see what they offer, i really hope its they have 3slot version like with the GTX680, but there was a 2 slot version also....

In the mean time, i been reading some for my build, and i found something interesting while searching for other stuff, the following is a X79 mobo but in the pdf manual that you can use the last PCIe for 2 way SLI,



So you might be able to do what you were initially planning with an XL-ATX case, just check the motherboard that you chose if you can use the PCIe slots for 2 way sli (not 3way not 4way).

Interesting. Most of the motherboards they seem to you want to use only 2 specific slots for 2 WAY SLI. If you had an XL-ATX motherboard with one more slot it would be perfect.

Mind if I ask which motherboard you have?

Asus Maximus IV Gene Z, its micro atx Z68 / Sandy Bridge mobo, you can see my build on my sig (micromi build). Planning on the ASUS ROG Maximus VI Gene (mATX Haswell Z87), i really want fanXpert2, mine only has fanXpert1 and i cant control the frontal fan,



I also have Fractal Design Define R4 on my way, so im still thinking on the Hero version, which is very similar to the GENE just in ATX, but to add a dedicated sound card and maybe a Prolimatech MK-26, but idk yet what im doing, will see how the DirectCUII comes out,

Some nice videos JJ at Asus that might interest you,

ASUS ROG Maximus VI HERO Motherboard Overview

ASUS GeForce GTX 770 DirectCU II OC Edition Overview

He is probably going to show the GTX780 DCUII soon, according to his comments inside the video, but also keeping an eye for Computex =)

In case you interested still, the ROG series are available for preorder.....

ASUS Maximus VI GENE $210
ASUS Maximus VI HERO $230
ASUS Maximus VI EXTREME $400

The GeForce GTX 780 DirectCU II OC is two slots wide

Dang it, you beat me to it!!

The question is, when will I be able to get my filthy hands on one?

I really hope SPCR gets one to review... its a totally new design, specially the fans... a little worried of that hybrid fan.... none the less looks amazing good for cooling with bigger fans, the question is will it be quiet.

Btw since you were in the Motherboard hunt, asus still had 2 mobos saved for computex, one of the is the formula. Im guessing it will be a $300 mobo to fill between the Hero n Extreme. Personally i have my reservations, the armor i was never fan, but details have to come out into how it is really.

Thanks. I've decided to hold off on replacing my motherboard for the new round of LGA 2011 motherboards with x99 chips. I would still like a decent video card until I get the new motherboard. Then, I can go ahead and buy a second video card for SLI.

The directcu 780 is the card I'm most interested in but get a feeling we won't even see demo/test units out for reviews any time soon.

Bad news...

TechPowerUp Review ASUS GTX 780 DirectCU II OC 3 GB

. Maybe it can be tweaked with their utility, but if they find it noisy... then it will be really bad for me.

I'm thinking on waiting for MSI Lightning or going with the Stock EVGA GTX780 + EVGA Backplate + Prolimatech MK-26.