So I got some great advice here about building a gaming machine. So I pretty much have an idea of what I want to get but I am unfamiliar with this SLI stuff. It seems that videocards like the GeForce GTX 285 and 295 are SLI compatible, but when I read their info it is confusing to me as to whether the card is ALREADY setup for parallel processing on the same card or if I’d need to get a second card to take advantage of this. Right now I am leaning toward the GTX 285 or a Radeon 4870. I’m trying to stay in the 300 range for the video card, but might go up to 400 if it’s worth it. I was previously looking in the 1000 range for my PC but have decided that 1500 will be better so I can pimp the video card and monitor.
Parallel programming is the bread and butter of modern GPU’s. Using stream processing they are like miniature cell computers packed into a single GPU.
With SLI and Crossfire (the equivalent ATI technology) two or more GPUs can be used to render a 3d scene in tandem. So if you have two GPU’s the first one renders frame 1, the second frame 2, then the first one frame 3, etc.
All modern GPU cards are SLIt/Xfire ready. All you need is another GPU OF THE SAME MODEL to run in SLI mode.
So two GTX 260’s or two GTX 285’s or even three GTX 285’s for Tri-SLI.
The GTX 295 is a special case (as was the 9800 GX2). These cards actually have inside them two sandwiched boards each with it’s own GPU, two cards inside the single unit. This card essentially runs SLI right out of the box as the computer will treat it (and see it) as if it were two separate cards.
If you were to buy two of these you’d have a quad SLI setup.
Of course these dual-GPU cards (like the GTX 295) have to make compromises in terms of performance due to heating and space issues. A single GPU in the 295 (if we for example turned the other onboard GPU off) performs similarly to a GTX 260, not a GTX 280/285. It also does not have available to it the full 1 GB VRAM buffer that the 280/285 has available to it.
The good thing about SLI is obviously that there is more muscle being used to render games. That means you can play at higher resolutions, with higher detail and higher image quality levels. The down side is that the performance boost is never 100% and it is also disparate, uneven from game to game, and even from settings to settings.
So in some games you may see only a small improvement in frame rate at the resolution and quality levels you were playing before you went SLI. But where as before you couldn’t turn everything on high and play at your monitor’s native resolution you find that now you can. Suddenly you see a 75% improvement not at the old settings, but at the new higher settings compared to when you were using only a single card.
Of course, as I mentioned this is not always the case. Sometimes you’ll find a game where the improvement just isn’t there no matter the settings, and (although much rarer) you might even see a game where you have to force SLI off before it plays at an acceptable frame rate.
Ahh alright. I am leaning toward the GTX 285 at this point.
Heh, I lectured you didn’t I? 
I went with the GTX 285 as well. Did you decide on an i7 or a core 2 duo in the end?
The GTX 285 is a really nice piece of hardware. The process used is the smallest the GPU industry is using right now and that means less power less heat and more overclocking potential.
I figured that in a year and a half I’ll just buy another 285 (probably $150+ cheaper) and go SLI for another year and a half before upgrading to another single card solution (probably a DX11 card by then).
I think core duo. Your plan to get a second 285 sounds like a really good one, I might think about that too.
When you get the second card can you plug in a second monitor to the port on the slave card?
Both cards have two outputs, you plug your second monitor into the second out on the primary card.
Sort of. Until recently in SLI(i don’t know about xfire) you could only have one monitor going at a time if SLI was enabled. You could disable SLI but still have two cards in and use all their monitor ports at once if you wanted but you wouldn’t get the extra acceleration from the second card if you did.
In the newer drivers though you can use all of the monitor ports on a single card at once with SLI enabled, but still cannot use the monitor ports on multiple cards at once with SLI acceleration enabled. So with a pair of cards like the 260(what i use) i could have 4 monitors going at once with SLI acceleration disabled or 2 at once with it on.
Just wanted to caution you that the average boost from SLI is along the lines of 20-30% according to a friend who makes drivers for video cards for a living. I would be shocked to hear of a 50% boost, let alone 75%. So in my opinion, it’s better to spend the money on a better card than run two cards. I’ve also heard a lot of people having problems with SLI and I suspect The Geek Factor is the only reason anyone does it.
Mwas, you’re primarily concerned with running Eve online right? A 285 is overkill for that game - although it’s a very nice card and I’ve no doubt you’ll be happy with it. Two of them, well, that’s like blowing up the entire middle east and everyone in it to kill bin Laden. Another point is your motherboard has to support SLI (preferrably two or more PCI-e 2.0 slots), and you better have a very nice power supply if you do decide to go that route. Also might want to think about getting a better CPU cooler than the stock one it comes with.
This - it can’t be said enough. Gaming is, and for the foreseeable future will always be about the fastest single core, and the fastest single GPU. Duel-channel RAM is IMHO about the extent of parallel processing where it isn’t cost-effective just to buy better, instead of more.
I suspect with computer hardware prices continuing to decrease and the seeming (subjective) plateau of system requirements, SLI is just another way to pump money from those who want the bleeding edge, regardless.
FWIW, any reasonable system less than two years old should run EVE flawlessly - the game is mostly static, if highly complicated, images and most of the strain it places on systems seems to stem more from inefficiencies than true demand.
I dunno about the CPU part these days; some games are starting to take advantage of multiple cores, in particular Valve’s Source engine. A dual core machine pretty much a necessity, and even quad-cores are starting to become winning propositions for gamers. At this moment in time I would recommend a faster dual-core over a quad-core processor, but that is beginning to change. There are plenty of games that push the CPU pretty heavily, especially with the trend towards more and more detailed physics simulations, and the only way forward for them is to begin parallelizing.
I totally agree about SLI though.
I’ve gotten much the same advice on Tom’s, Anandtech, and other places (and probably from some of the same posters here). I’ve been in the position to add a second card (SLI) or upgrade the single card – and after a lot of asking and reading, it seemed the biggest improvement would come from the single-card upgrade. Yes, there are some situations in which SLI would be vastly better, but as noted upthread not in every situation, and at best it’s not like getting twice the card-power.
So backing down on cost let me get a single card that works a lot better than the two lower-side SLIs (i.e., budget movements for 2 x $300 cards v. 1 x $500 card) to get better results almost all across the board. Note you’ll also have the option to save on PSU, cooling, and a non-SLI board.
As I mentioned, SLI improvements in performance (and yes I have personally seen upto 75% in some games) do not kick in until you start increasing graphics quality, turning on image quality filters (AA & AF) and playing at higher resolutions.
Case in point:
Back when I had my 9800 GT I could play Crysis at 1440x900 medium settings at a good clip. When I upgraded to the 9800 GX2 (two 9800 GT’s in SLI essentially) I saw about a 20% increase in performance at those SAME settings.
Going up from medium to high and incresing the resolution to 1680x1050 gave me unplayable results with a single 9800 GT, but with the 9800 GX2 I could again play at a good clip. The difference in FPS was about 60-80%.
Is that a typical result with SLI? Yes and no. So far every time I’ve dabbled with it the overall result was the same: I could play at higher resolutions, with more filters and options on. But will that always translate to a 50% + improvement in frame rates? No, it will differ from game to game and from settings to settings.
Pretty well covered (and I covered it in your original thread) that it’s pretty much always a bad idea to buy 2 cards at once to do SLI. For the same money, buying a higher end video card is the better option. SLI just doesn’t work that well - you get 10-30% more processing power rather than double. In some applications it’s less than that and in some cases you actually get a performance decrease because of driver/compatability issues. There’s also a problem I’ve heard of (but never seen) called microstuttering - frames coming at an uneven rate as an artifact of SLI that’s supposed to look bad.
The only time SLI should come into play is when you’re a rich idiot and decide you want an $8000 computer and 2+ top of the line video cards is the fastest you can get, or you buy a video card now and then down the road when you get a chance to get another card of the same model for 1/3rd the original price you add it to your current setup. Even then you may just be better served getting a new card.
Well I wasn’t so much thinking that I wanted to run SLI, I just didn’t understand what it was, and I wanted to make sure I wasn’t going to buy an SLI card like the GTX 285 and find out that I needed something else. I’m looking at the 285 because it’s not horrendously expensive, but should I decide I want to play Crysis I can. Eve is my main consideration, but if I can do more than Eve that’s cool too.
So any concerns regarding the GTX 285? I’m really leaning in that direction.
As I said the 285 is essentially a GTX 280 but it uses a 55 nm process (the GTX 280 uses a 65 nm manufacturing process) which translates into less power consumption (in fact the card uses 2 4 pin PCI xpress power rails compared to the 4 + 6 pin of the GTX 280) and a cooler and quieter product.
This also means the overclocking potential is greater. And performance right out of the box is a bit better than the GTX 280.
Most importantly, perhaps, is that you can find it cheaper than the 280 in many places. So it’s a no brainer for a high end system.
The 285 is a very nice card and should run new games for you for quite some time.