Thinking of a new system

Here is a review on your exact question http://www.tomshardware.com/reviews/crossfire-sli-3-way...

It is a mixed bag really. It appears a 3 sli setup preforms best at larger resolutions and AMD has the advantage. I personally feel the cost outweighs the benefit.

If you want to better future proof your rig pick up a card with at least 2gigs of vram.

The 2500k is all you need for a gaming rig. If you do not plan on overclocking save a little more dough and pick up just a 2500. You would only need a 2600 or 2700 if you used applications that took advantage of multi-threading.

I have 16gigs of ram. Is not necessary to have this much but ram being as cheap as it is I said why not.

Yeah dont talk about anything over a 2500k, save your money and invest in somthing awsome.

All comes down to monitor size. If you're running 2560x1600, get a single 7970 or maybe a pair of 570s. If you're running triple 1080p monitors or higher, you might be able to use the 560Ti 448 tri sli power, but you'll be short on VRAM. Better go with tri crossfire 6950 2gb, or SLI 580 1.5gb (or 3gb), 590 3gb, or 6990 4gb. CF 7970 3gb would be the most powerful of course, but that comes at a crazy cost of over $1100.

yea, some games, but one of the reasons i'm looking at a 2700k is i also use the media center stuff all the time, between recording 2 and sometimes 3 hd channels at a time, though i know its not done by the cpu but i get it, if it was just for gaming sure, 2500, but thats not all i do. and as most gamers sometimes i play games while i watch tv in the media center while browsing the net, thank god for multi tasking. but given the story, even though i have had bad luck and generally bad feelings towards amd in the past, maybe i should look into them again for crossfire, well maybe. as far as resolutions go. right now i have one 1080 moniter and one running 1366x768, but i'm thinking of getting a second 1080 moniter and running 3 screens, the 1366x768 is an older 32 inch 720 tv the 1080 is a 24 inch. though i dont need to replace the tv anytime soon, if i need to i'll just get another 32 inch, but 1080 tv.

and one more question. i know some of you were talking about the ram on the cards. as it stands the cards i'm looking at is in the 1.2GB range, and i right now run an older card with 1GB, i do remember the stories of how the 92 chip on the 8800 gt cards couldn't make due with the 1GB of ram on the card., but i also figured they would through driver improvements over the years they would be able to, at least to a point. but with 16GB on the mobo, wouldn't the video cards be able to get the extra they need from the system ram through shared memory? sorry if i sound kind of dumb. i did a ton a research when i built my last system but that was a long while ago. i have watched the tech trends over the years, but i'm in no way a "tech geek". and i mean "tech geek" in all the best ways possible. as it stands, i figured the 1.2GB would be enough and the extra needed it could get from system ram, is this though wrong?

For 1080p, you'd be throwing money away with tri SLI. A single 580 or 7970 can easily max out the graphics in any game at that resolution, and then you don't have any possible issues with lack of SLI support - or lack of tri SLI support - or micro stutter, or anything.

Adding more monitors isn't a big deal unless you plan to do multimonitor gaming, in which case you really don't want to try it with a mismatch of screen sizes and resolutions.

As for VRAM, yes shared system resources helps alleviate the issue. I run 1gb cards in crossfire and have no issues, and I've seen benchmarks of the games I play using more than 1gb of VRAM. So obviously shared resources works. However, it does induce some lag, and I have noticed when it needs to do a full memory flush to load all new textures and such that there will be a large drop in framerate for a couple of seconds, before launching back up to 60+.

1.2gb is fine for 1080, but 1.5-2gb is definitely more "future proof".

Cheers on building a new rig- always fun and exciting. With regards to looking at different things and what's "worth it", you have to realize it's a very subjective measure. Here are a few things to keep in mind:

- The 2500k is a quad core processor, but can't use 8 threads like the 2600k/2700k (which use hyper threading to double up). For what you're doing I would echo these other inputs and recommend going for the 2500k and saving the additional $100+ to use on other parts of your system.
- The 560 ti 448 core is NOT a bad card, but it's sort of a funky one. It's a limited production item and there are no guarantees on availability long-term. Say you have a warranty issue and it has to be replaced- well you may not get another 560 ti 448 back. I'd honestly recommend bumping up to the 570, especially if you're shooting for a super-high end system like this.
- If you're not playing on an enthusiast display (by that I mean multi monitor or a high res monitor w 2560x1600) then I'd highly recommend you start looking into it. This build is a lot of performance to throw at a single 1920x1080/1200 display.
- People talk about VRAM a lot, but I've yet to see a compelling argument (supported by comparative benchmarks) showing that the higher VRAM versions of cards provide substantial benefit even at higher resolutions. Most items I've seen linked are less powerful 1GB cards compared to more powerful 1.5+GB cards where the VRAM isn't necessarily driving increased performance. My advice would be to stick with the "standard" VRAM on whatever card/cards you choose (whether thats 1.25GB 570's, 1.5GB 580s, or 3GB 7970s).
- Lastly, realize that no matter your resolution, this much power is overkill in most games. I'm absolutely not saying you shouldn't do it, just understand your wants/need and think about if it's worth it to you.

Looks like you are planning to spend $1800-$2000 on a new system. My suggestion is to wait 2 months until Kepler is out or at the very least we get an idea of the performance via leaks. If you wait till May then Ivy bridge will be out and it will perform 10-20% better than sandy bridge. The 7970 will drop in price by then as well because it will have competition...a few early leaks say the successor to the GTX 560ti will be within striking distance of 7970.

Basically, if you're spending $2k its best to buy products when they are released rather than ones at the end of their life cycle...keeps things a lot more future proof and you know that you bought the best from that generation. Also, there aren't any new games that are forcing you to upgrade immediately. Oh and GTX 560ti 448 is a terribly priced card...its best to get a GTX 570 if you really need it now.

new question, as far as pci-e 2.0 is concerned, i pretty much decided i'm going to just run a set of gtx 560ti 448 core cards, those are pci-e 2.0 cards. i been looking around trying to decide on a mother board, but one thing i keep seeing is they list 2, 3 or 4 pci-e 16 slots but note that when a 16x card is installed in the first the 2nd, 3rd and /or 4th slot go to 8x, is this going to be an issue for that? i am pretty sure i'm just going to run a intel i7 2600k. i was looking at a few different asus motherboards, and a msi at this point. i tries to look this up before i asked this here but couldnt find an answer.

Basically the 1155 socket CPUs have only 16 PCIe 2 lanes in them to hand out. Most motherboards divide that up between 2 PCIe slots, so you get 16x single or 8x/8x double. Some cheap motherboards run it at 16x/4x, but basically what this does is runs the 4x through the south bridge rather than the CPU.

There's also motherboards with for example 2 pcie 16 slots (16/0, 8/8) and a third one set to 4x. Again, the 4x runs off the south bridge.

The south bridge controls the 4x slot (if there is one) but also all the 1x slots and the SATA and USB bandwidth.

Anyway, to actually answer you, running at 8x/8x will reduce your performance by around 2% compared to 16/16... so basically not at all. I might worry about it if I was running a pair of 7970s but for 560Ti 448 it won't matter.

There are pricey motherboards with an NF200 chip, and basically that copies PCIe bandwidth to double the lanes to an effective 32 lanes. This ONLY works with GPUs though, because they require identical info. Typically these will therefore have 4 PCIe 16 slots with various configurations like 16/0/16/0, 16/8/8/0, and 8/8/8/8. This is only really useful to run 3 or 4 GPUs.

thanks, i looked for a while before posting this question. then looked some more then found the info. the system i have now is the old striker 2 formula with the nforce 780i that does run the pci-e at 16x on both my 8800gt vid cards and was worried that it would bottleneck. but from everything i seen the loss will be so small i doubt i would notice, even if my current set up was even close to the what the new setup will be, so pci-e 8x in sli with the vid cards i want will still be better then what i got. thanks for the info.

ok i just thought of something else, with the integrated graphics on the 2600k and with most of the motherboards having a dvi or hdmi connection, can i use the dual vid cards in sli to run 2 monitors at that 1080 resolution and run the 3rd display off the integrated graphics through the connection on the motherboard? like maybe the asus p8z68-v? would it be a benefit or hamper performance considering the 3rd display would be running at 720 resolution, strictly as a media display for blu-ray and whatnot for hdcp compliance. i do understand the 560ti 448 core cards normally have at least 2 dvi output and an hdmi output. but will be running different resolutions and i couldn't get sli to enable with 3 monitors. and i have seen other people having similar questions. but the questions didn't really apply to the integrated graphics in the intel 2600k.

With SLI you can run up to 4 monitors off your GPUs, but yeah with the Z68 chipset you just download and install the Virtu Logix software and it allows the integrated GPU to be used. Although I've never used it for a display output, but it should work. The main intent of that feature is to use Quick Sync.

Performance shouldn't degrade any if it's just at desktop. I run a 1280x1024 second monitor off my GPUs and FPS didn't change much if at all. And I would think running a monitor of the IGP would do even less to performance, unless maybe you try playing a movie off it while gaming.