TR Forums

I am in the midst of doing my first PC build and need some info on a dual-card set-up. Specifically what sort of user is it best suited for? I am a avid gamer and would love the extra boost to my experience, I just don't want to overspend for a modest gain. For example Is it better to invest in a high-end 6990 or go with two 6950s? What are the basic pros and cons of single vs. dual?
Any info is much appreciated.

Edit: I should mention that I plan on using one monitor for gaming. I may at some point hook up my 27" LCD TV with my new ASUS 23" monitor just for giggles; maybe to multi-task movie watching with web browsing but I doubt I will invest in the proper two monitor set-up to game with.

So that we know you aren't skimping on equally important components, do you have a rough outline of the system you plan on building, as well as a total budget and the games you plan on playing?

Considering the resolutions you plan on using, anything more than a single 6870 would probably be overkill, and that's only if you plan on playing the latest and greatest such as BF3, Witcher 2, Rage, etc.

I will probably get an Intel i5 of some sort since the I7 line seems like overkill; also I plan on having 12 gigs of ram. Thanks for the response, thats what I am looking for. I am looking to spend somewhere in the $1500 range for everything so I have a little bit to play with. From the sounds of it going with a single 6870 seems like the best value. The 69XX is tempting, but like the i7, from what I have read the gains don't seem to be that much over the 68XXs. What would be the minimum amount of voltage I would need from a power source? Currently I have a 650 watt model earmarked.

Unless you are using the hell out of AutoCAD, there's no reason to have 12GB if RAM. 8GB would be more than sufficient. I would also go with a power supply in the 500 - 550 range with a 80 plus certification, preferably 80 plus BRONZE. Almost anything with those specifications will deliver plenty of good, clean power to your system. Besides that, my only other recommendation is to consider a SSD for your OS and whatever programs you can fit on it. A big as you can afford, and make sure it's from the latest crop of SATA III drives. That will significantly cut your load and boot times.

I used a 6870 crossfire config until just recently and it played just about every game maxed out at 2560x1440 (Dell U2711). Only Crysis 2 DX11 HTP gave it any problems and even then it was quite playable at Ultra. 1920x1200 and below should be a walk in the park for most games.

It'll also help if you have an idea of what games you plan on playing. It'll probably be best to build for the most strenuous game you want to play. For instance, Shogun 2 Total War will eat as much CPU and GPU power as it can if you play on higher settings (and really, what's the point of total war if you aren't playing on Huge scale). I have 2x6950 and the difference between single and dual is like night and day, but there is microstutter which is annoying. SC2 will favor a stronger CPU over a GPU. Any FPS made in the last 5 years will run well on pretty much anything thanks to the magic of cross-platform releases. So since you have the money, it'll be worth finding out what the most demanding game you want to play is.

Not to take the topic off-track here but if 550 watts is sufficient for the type of system I am getting then what DOES justify some of the higher watt power-sources? I see the top-selling power sources on newegg all generally fall into the 650 - 850 range. I am somewhat of a green-minded person so the prospect of running the system as low-energy as possible (and as quite as possible!) is appealing but I also don't want to plug in all my components and begin to have issues on my first build.

Also I will switch down to 8 gigs if there really are no noticeable gains for what I using the PC for.

@ Zoom: I am building this to play Battlefield 3 and Deus Ex (of course!)

I also want to finally go back and play GTA 4 with settings maxed out; a dream of mine after giving up on my first play-through for proper hardware. Also SCII, any valve game (which can usually run on most anything) and I might check out Rage. I don't see myself playing any of the Total War games; basically I play a lot of newer releases and want a card set-up that is going to last 3-4 years at least (my current one just turned 3).

So while you say the gains on a game like Total War is noticeable am I going to really notice a HUGE difference overall? For about $160 i can get a 6870; will spending $320 all together give a respectable difference with most modern games?

It sounds like you have wiggle room in your budget to get a matching monitor and go dual-screen, and still have cash to spare. Have you thought about that?

grantmeaname wrote:

It sounds like you have wiggle room in your budget to get a matching monitor and go dual-screen, and still have cash to spare. Have you thought about that?

What games are going to benefit from dual-screen. I didn't really monitor-shop with dual-screen in mind so I really don't know how well suited my current choice is and if the monitor rims down the middle are going to drive me crazy or not. That is my main determent from it is the space in the middle, though I have no play-time to back this up, just a general feeling.

ALiLPinkMonster wrote:

Unless you are using the hell out of AutoCAD, there's no reason to have 12GB if RAM.

Does one need a reason with DDR3 prices this low? I'd pick up 12GB in a heartbeat!

gecko575 wrote:

Does one need a reason with DDR3 prices this low? I'd pick up 12GB in a heartbeat!

If he wants to spend money for no reason that's his business. Personally I would much rather head to the local pub and have a few beers with that money.

i7s on socket 1366 are triple-channel, so that means he can choose between 6GB or 12GB, and he's likely doing the latter.

Now if you ask me if he should go with an i7 to begin with, I'll flatly say "no".

You should read this article first before dropping from 12GB to 8GB. http://www.tomshardware.com/reviews/ram-memory-upgrade,2778.html

Their idea of using extra system ram as a ram drive to hold the swap file was interesting. They also tried disabling the swap file entirely with interesting results. You might decide 12GB isn't enough.

As for power usage, you should check into this site to get an idea of how much power you'll need for a dual video card setup.: http://extreme.outervision.com/psucalculatorlite.jsp

MEKsLP wrote:

What games are going to benefit from dual-screen. I didn't really monitor-shop with dual-screen in mind so I really don't know how well suited my current choice is and if the monitor rims down the middle are going to drive me crazy or not. That is my main determent from it is the space in the middle, though I have no play-time to back this up, just a general feeling.

In my experience, dual screen is irritating for FPses but really quite nice and not too irritating at all for RTSes. For an MMORPG (even a complicated RTS), you could use the second for information or maps, of course.

morphine wrote:

i7s on socket 1366 are triple-channel, so that means he can choose between 6GB or 12GB, and he's likely doing the latter.

Now if you ask me if he should go with an i7 to begin with, I'll flatly say "no".

He said something about an i5, so I think the socket 1155 is what he had in mind, no?

Regarding RAM, you can always get 8GB now and 8 more later, if you see a need for it. Just make sure you get the 4GB modules. (Tho, I like the idea of RAM driving the swap file, checking it out now.)

Regarding power supplies, big wattage is not the answer, it is the efficiency that is important. Bronze rating is good.

If you want speed on OS start-ups and game loading, get a SSD, it is worth the money. With a 1500 budget, you can get a nice 256GB drive that will hold you OS and most of your games. But that is just my opinion, but I know from having one that it makes a ton of difference. SATA-II or SATA-III notwithstanding. Tho, to stay ahead, I would go with SATA-III to stay ahead of the game.

Video cards is a hard thing to shop for. It is important to read up on reviews. Most, test with games. Just remember that dually cards have there problems. Just remember that it seems that 57xx are more powerful than 68xx, but more power hungry. And the 69xx are more powerful than either and a little more power hungry. And of course, the price is effected.

This is what I would do, I would go on Newegg just to build the dream machine and then play with the prices by upping or going down on parts/prices. And save them on wish lists, even if you don't buy it from there.

Just my 2 cents. And good luck and keep bouncing things off us.

SomeOtherGeek wrote:

He said something about an i5, so I think the socket 1155 is what he had in mind, no?

Correct, I misread what he typed. So 8GB it is, IMO.

SO!

For now I think I will avoid a dual-screen set-up. It sounds nice in some ways, and if I want the benifit of multitasking I can still plug in my LCD TV, it just won't work for spreading games across the two. I personally want my games to look AMAZING on one screen without the black bar in the middle...not to mention I can put the extra money into better hardware.

So I took the test for power usage and was at around 400 watts for my low-end estimate and 500 watts for my high-end (if I ever decide to get 16 gigs of ram and two cards, etc). The biggest thing is that I like the look of the Cosair power-sources and the smallest one I can find is 650; I am also going modular with this as the idea of having as few cords inside the case as possible is very appealing. I may end up going with a lower-watt Cooler Master and will of course make sure its Bronze certified (are the silver, gold and platinum certifications worth considering at all or overkill?)

I think I am steering away from the dual-card set-up. It sounds cool in theory but I want something that runs smooth every time (I will probably avoid over-clocking for this reason, it seems too imprecise and error-prone for my taste). I am still looking at the 1 gig 6870s for now, I was considering a card with 2 gigs of RAM but have been told from multiple users that its only necessary to have that much if I plan on running insanely high resolutions...still if I find a deal on a 69XX I may dive in...the 68XXs are so damn cheap comparatively on Newegg though. Seems like money invested in a bigger SSD would make more sense.

I do plan on getting an SSD though I am not sure which one yet. For now I have all these items saved in a Newegg list so I can sale shop over the next 4-6 weeks; that is how I went about getting my monitor as it had an insane deal on it. Right now I am at about $1550 with an i5, 8 gigs of ram, 6870 ATI, a nice keyboard/mouse set, a 120 gig Intel SATA II SSD (though this pick will probably change), my 650 power supply, card reader, CPU fan, a tentative ASUS MOBO and the Cosair white 600T case. Now I know if I don't get impatient that I could potentially shave a couple hundred dollars off by sale shopping all these items on Newegg and get under the $1500 mark and maybe get 12 gigs of ram or a bigger SSD.

Awesome! Your ideas and thinking is sound. Yep, the hard part is being patient! Heh heh. Have fun and happy building.

If you're going to play on a single monitor, yeah, a 1GB card like a 6870 is all you need. When you get into 3-screen gaming you'll need 2GB+ cards. HardOCP did some testing with Nvidia's 1.5GB cards and they did great on single screens, but couldn't keep up on 3-screen displays compared to an AMD Crossfire with cards having 2GB of memory.

I have a Sapphire 6870 driving a 24" monitor @ 1920x1080 and it runs everything I throw at it at max settings.

As for power supplies, I highly reccommend you read some reviews at HardOCP. http://www.hardocp.com/reviews/psu_power_supplies/

You'll learn a lot about power supply construction and see how some brand names we've all come to love don't really design and build their power supplies. They outsource the whole thing to the lowest bidder, slap their name on the box, and call it a day.

I ended up buying a Seasonic 750.

someuid wrote:

If you're going to play on a single monitor, yeah, a 1GB card like a 6870 is all you need.

Not true for all resolutions. I bet some recent games, if not the upcoming ones, will need more than 1GB with 1920 / 2048 / 3560, especially with AA involved.

I have dual crossfire with Radeon HD 5870 running 30" monitor at 2560x1600. Overall I am satisfied with performance. However as you probably know multi-gpu setup is software dependent, so there are occasions when you have to sit and wait for either AMD or a developer to update their code to take advantage of 2 or more gpus. It is very common with newly released titles. Keep in mind some games just don't scale well with multi-gpu setup, Crysis is one of them. STALKER Call of Pripyat Complete mod does NOT work with crossfire when texture quality is maximized the game simply crashes before it loads.

I would rather go with 2 cards rather than 1 card with 2 gpus for 2 reasons: 2 cards perform a bit faster, if one card fails you still have the other to get by until you receive replacement (provided it is still under warranty).

You need to consider a more powerful PSU, I have 875Watt, but I would go even higher maybe up to 1200Watt simply to get quieter game play because it gets quite loud. The noise level between single and dual cards is very noticeable indeed, I played with a single card for a while, I can tell.

If you can, wait for HD7000 series it is only a few months away.

P.S. I just installed Catalyst 11.8 preview drivers and long awaited issue with STALKER Call of Pripyat Complete mod is fixed !!!!!!!!!!!!!!!!!!!

morphine wrote:

someuid wrote:

If you're going to play on a single monitor, yeah, a 1GB card like a 6870 is all you need.

Not true for all resolutions. I bet some recent games, if not the upcoming ones, will need more than 1GB with 1920 / 2048 / 3560, especially with AA involved.

I agree. Getting a card with extra VRAM is probably a good idea at this point. Oh and don't listen to most of what michael said unless you plan on getting a 2560x1600 monitor.

A 2GB 6950 or 6970 should do you very well for some time if you are only going with 1920x1200. Probably better than crossfire since not all games have proper support for crossfire, etc. Unless you are shopping now, theres new ATI cards out this autumn, so the current cards will probably be a bargin if you have a limited budget. 2GB is for having high AA/AF on higher resolutions. That quickly eats into your ram. But at least 1GB VRAM is a must today.

I have a Dell u3011 30" and runs all games on my 6970 at 2560x1600(4MP), Bad Company 2 works fine, but I usually go down on AA a bit just to not hinder the card too much. 4MP is a decent amount of pixels to push. The only game I have to run at something lower is Crysis2 which runs at 1920x1200(2MP) at High with decent framerates. But the difference between the two resolutions is almost double the pixels and the lower isnt really two times as fast.

michael_d wrote:

You need to consider a more powerful PSU, I have 875Watt, but I would go even higher maybe up to 1200Watt simply to get quieter game play because it gets quite loud. The noise level between single and dual cards is very noticeable indeed, I played with a single card for a while, I can tell.

I'm using a 650w Seasonic Gold with my two HD6950's- no worries there. Quality of PSU matters here more than wattage, just make sure that it comes with the proper PCIe connectors.

Airmantharp wrote:

michael_d wrote:

You need to consider a more powerful PSU, I have 875Watt, but I would go even higher maybe up to 1200Watt simply to get quieter game play because it gets quite loud. The noise level between single and dual cards is very noticeable indeed, I played with a single card for a while, I can tell.

I'm using a 650w Seasonic Gold with my two HD6950's- no worries there. Quality of PSU matters here more than wattage, just make sure that it comes with the proper PCIe connectors.

yeah I am going to stick with something in the 600-700w range. I am going to try to wait on the ATI 7XXX series for price-drop alone but I am getting desperate. I have the money set aside for the PC and the one I am currently running has some corruptions in Windows 7 and needs a reinstall plus the graphics card overheats routinely (I think its a 48XX) and if that doesn't then the processor does; a dual-core that is 6 years old. I haven't been able to play a game properly on my PC for almost 10 months; woe is me, i know. I need some LFD damnit!

whew

so anyway, I will try to wait on the graphics card and sale shop the rest of this stuff in the meantime. Thanks for all the help so far!