Last Saturday during boot-up my motherboard had a "Burn-out" (Bright flash accompanied by a 'Poof' of smoke... oh the humanity!!!). Thank Talos I bought the extended warranty! Anyways, I'm rebuilding and taking the opportunity to upgrade a few of the components (Mobo, RAM and GPUs) to the following build:

Motherboard: ASRock Z68 Professional/Gen3
CPU: Intel Core i7 2700K [OC'd]
Hard Drive #1: Western Digital VelociRaptor [300GB @ 10,000 RPM]
Hard Drive #2: Intel X25-M SATA II 80GB SSD
Hard Drive #3: Intel 510 Series SATA III 120GB SSD
Hard Drive #4: Western Digital VelociRaptor [300GB @ 10,000 RPM]
Memory: Corsair Dominator GT 16GB @2033MHz
Power Supply: 1000 Watt Corsair HX Silent Edition
OS: Windows 7 HPE, 64 bit

Only thing left to decide on are the GPU(s).

As Skyrim is, and will be my most played/modded game for some time, I don't mind catering my build to best accommodate it. I realize it's very CPU dependant, but for the GPU's, I'm leaning towards going with two HD 6970's in CrossFire (Have read they scale better than two GTX 580's). My question is: "Does the Catalyst 12.1 driver even offer CrossFire support for Skyrim?" (Or do the latest nVidia drivers support Skyrim in SLI?) Would I be better off going with a single uber card like the HD 7970? Thoughts?

Thanks in advance.

Just get a 7970. Less power consumption, less heat generated, quieter, and will run better, due to not needing scaling support.

FWIW, I'd look into paying a little more for extra VRAM, too, if you can find a model that you like. I just upgraded to a 570, and it runs the game great at 1920 x 1200 with ENB at ultra settings, but I've run into VRAM limitations, and I have to be careful about installing new textures (I'm at about 3GB of hi-res texture mods right now).

If your worried about VRAM buy a beefy card, but personally when I rebuilt I spent like ?$250 for a 560 ti gtx twin frozr II, maxes skyrim, and bf3 with a hearty OC, and personally I just bought that as a placeholder till the 6XX arrive. It will do everything you want it to do, haven't ran into any issues with lacking VRAM as of yet even with oodles of texture replacers, and it's not very expensive. IMO the 560 or 570 is where it's at ATM, 580s aren't worth it imo, the 590 is beaten by two 570s, and the 7970 is bleeding edge hardware, usually unwise to jump on the bandwagon early, never mind cost, haven't looked because I could care less about ati, but I'm sure it's about $600.

Aside from using a little less power than a 580 (what's 50watts if you're building a gaming rig anyway?), the 7970 is more expensive, runs hotter and is noisey as hell.

http://www.tomshardware.com/reviews/radeon-hd-7970-benchmark-tahiti-gcn,3104-17.html

OP, you may want to wait, nvidia's new series of cards should be released very soon.

get a 7950 3gb

It'll outscale the very great scaling 6xxx series gpu's in crossfire... skyrim doesn't like crossfire at all nor SLI all that much

with texture mods.... reaching and even exceeding 2gb vram is quite easy to do.

the Non Refference 7950 3gb cards perform excellently and don't generate nearly as much heat.... and are much cheaper.. it performs about 30-40% faster in some cases than the equivalent 6xxx card.



Heres a good example of a bunch of the newer 7950's compared to older generation and even the NVidia 580's

http://www.hardwareheaven.com/reviews/1392/pg2/sapphire-radeon-7950-overclock-edition-vs-7970-oc-vs-gtx-580-oc-vs-6970-oc-review-the-card.html

A lot more thorough than tomshardware

Power consumption/ Heat/Noise levels are significantly lower that any of the other cards http://www.hardwareheaven.com/reviews/1392/pg11/sapphire-radeon-7950-overclock-edition-vs-7970-oc-vs-gtx-580-oc-vs-6970-oc-review-power-temps-noise-overclocking.html

Thanks for all the responses and links guys! Lots to consider.

DHJudas, you mentioned "Skyrim doesn't like crossfire at all nor SLI all that much". Am wondering (and anyone else feel free to chime-in here) what are the ill-effects of Skyrim w/ CrossFire and/or SLI? With AMD, I thought I read somewhere (or maybe not) that Catalyst v12.1 fixed CrossFire issues. Also, if CrossFire and SLI are problematic w/ Skyrim, what are the chances of issues being resolved either officially or through fan-made mod utilities?

I agree, if you are hoping for excellent performance from crossfire or sli, you might want to rethink if it's for skyrim.
Skyrim is not the only one that suffers from scaling issues using two or more cards.
You'll often get better performance out of a higher end single card than 2 working together at the same budget.
Also you'll have more vram to stuff those textures into, so really it's a win-win.

Common problems, either it flat out doesn't work or their is micro-staggering, which is hard or at least not easy to fix or ignore.

So agreeing with DHJudas, get a nice beefy 3Gb+ card. You'll be happier in the long run.
Can't recommend on that high end, don't have enough experience with them.
Worst case scenario, is a year from now you buy another one of them and cross-fire/sli it then.

The 7970 is currently the best top end card and unlike what others have said in here, does not run noisy OR hot (unless your system is badly cooled). After playing Skyrim: peaked at 77C, fan peaked at 44%. It can do Skyrim just fine and quietly too.

You won't need more than the standard amount of VRAM (1.5GB or 2GB, depending on vendor) unless you're using multiple displays. I have a GTX 580 1.5GB and with the high resolution texture packs and uGrids set to 7, I'm using about 1000MB of VRAM consistently. 3GB cards are a waste for single-display gaming.

Again, thanks guys.

Leaning towards the single card option, but just to solidify things in my mind, I'm still wondering what specifically the CrossFire/SLI "issues" are. Do multiple cards in Skyrim just flat-out not work forcing people to disable CrossFire/SLI, or do they work but suffer from inefficient scaling, or graphical anomalies or what? If they work but have issues, can the issues be fixed/dealt with/overcome (or if not now, will they be)?

Forgot to mention in my OP the display I'm using is a single 44" LED TV @ 1920x1080.

For most people you do NOT need to disable SLI/Crossfire to get the game to work...these are rare exceptions. I have 2 computers running Skyrim...a 5970 which is 2 gpus crossfired within one card...and a GTX590, which does the same in nvdia-land.

There are some issues that are believed to be associated with SLI - such as microstuttering under very specific conditions - but for my understanding I have not seen any 'official' or 100% proof that SLI is the cause (although a hell of alot of anecdotal, including my own experiences)...there are ways to mitigate some of these issues that do not include disabling one gpu. In fact, when I disable one gpu, the game does what it is supposed to...go from a steady 60fps to about a steady 30.

As an aside, IMHO, to go with the sweet setup you are planning with a monster gpu, using a 44" LED TV seems like a wasted opportunity. Clearly, you are opening your wallet for this venture, so if I were you I'd go smaller and get a proper pc monitor...I high quality 23" or even 27" at even higher res will look ALOT better than your 44" TV for pc gaming. Or even swankier, 2 or 3 monitors for your eyefinity/whatever surround setup on 23 inchers.

Nearly the same @my rig, but:
1. I don't have the new official HD texture pack yet
2. I have about 3 GB other HD Texture MODS installed

and my Gainward GTX580 3GB goes at nearly 1500-1600MB VRAM usage while playing (more than a 1,5GB card can handle).

I think it maybe not enough VRAM, if you use the official HD textures and lots of more other HD stuff.

From the few discussions i have that deal with driver development from these 2 different brands.... essentially they have to do a lot of driver manipulation to make skyrim work properly.. and it's a tough game to play as skyrim refuses to play nice in this realm. Many of the people reporting that their crossfire/sli is working.. aren't... or they are but not properly..... or who knows what issue they are either ignoring or aren't aware of. Of course there seems to be the rare... very very rare occasion where it appears they have no issues at all with it or just "tollerable" ones.... I can tolerate a lot but i drew the line after about 15 days of irritation.

The basic symptoms i'm experiencing with sli and Crossfire is irratic frame rates and excessive random lags.... even with vsync and fps limiters in place to keep things more stable, the sli/crossfire modes are just to unpredictable resulting in even the physics of the game screwing up so horribly that it results in death in game or other npcs dieing, being tossed around like someone took the skyrim world and gave it a good shake every so often. Graphical anomalies include everything from weird colors to distortions or jitter, I've experienced some cases where the screen will flash in specific places, or will freeze solid for a few seconds and then appear to play catchup. The numerous symptoms experienced is hard to list as it's as i said, unpredictable.

Even though driver "fixes" have came about and continue to be worked on, an honest opinion from both NVidia and ati "unofficially" and i'm sorry i can't source it, but the unified statement was essentially that "don't expect sli/crossfire to be bug free anytime soon or ever"..

It's just the way the engine is, DX9c based engine with it's own quirks... it's hard enough to get FSAA to work properly in the game, at least skyrim has the option for FSAA..... This is why i moved from the dual/triple Crossfire 5770 1gb cards i was useing which performed on average as good if not better than my current 6950 2gb when crossfire works.

Skyrim is just a solo video card type of game. Every attempt I've made in several generations of video cards to get crossfire or sli to work has been a total failure. Even when i thought i got it working, a few minutes in would just become unstable again.

^^^ Wow! OK, thank you very kindly for that most thoughtful response. Most helpful.

Single GPU it is!

Wondering how soon the latest Nvidia cards are expected to be released? I'll have to do some research and try and find out. So it'll either be Nvidia, 7950 or 7970!

Cheers!

From my many years of experience I would go with the best SINGLE GPU Nvidia you can afford. SLI/Crossfire always has issues especially the annoying micro-stuttering and Nvidia's drivers are almost always more solid than AMD/ATI.

I think it is safe to say the SLI problems and crossfire problems are not necessarily related, and that problems with one are not necessarily problems with the other. I think that one must be careful making big gpu purchase decisions based on generalizations that blanket both without evidence.

I'd either wait for the Kepler cards to be released, or the mid-range 7000 series.

But, I've been looking at this myself.

As it stands now, I think a GTX 560 Ti 2GB would be your best bet. Enough VRAM if that's an issue, plus it's a solid card that isn't too expensive.

I'm running a 1GB XFX 5870 and running into VRAM issues with HD packs.

Speaking of the upcoming Nvidia GTX 6xx series, I've read a leak the flagship (Single) GTX 680 will only have 2GB Vram (http://www.tomshardware.com/news/Nvidia-Kepler-GPU-GeForce-600-Series,14642.html) compared to the 7970's 3GB. First off, has anyone seen definitive confirmation of this (680 only 2GB)?

Overall, the 680 will surely best the performance of the 7970 (Assumption). However, hypathetically with only 2GB Vram, would I still be better off going w/ the 7970 (Due to 3 GB Vram) with the thought of modding/texture upgrading the fool out of Skyrim in mind?

Thoughts?

Opinion noted...

NVidia's drivers are no more solid than ati's... and vice versa...

With Skyrim 2K and Bethesda's HiRes pack installed (as registered BSAs in Skyrim.ini), and uGridsToLoad set to 11, I've maxed at 2634 MB of VRAM used. If you want the best out of this game, get a 3 GB card.

Just dont get hd 6950 2GB.

As it seem to generate more heat. I run it with hd lite 1.4, some hd cloth, animals, waters, armors and male female high res replacers on custom high setting. Skyrim launcher auto detection seem to detect as high with a few ultra high auto detection (due to new skyrim.ini)

Upon playing awhile or 8 hours, after a check on temp after exiting the game.

My temp is about 65 degree. It might be higher during gaming which i suspect as i dont do alt tabbing.

I read about other with hd6970 with a temp of 49 on ultra high. I was like wt..

As long as you keep under 90 I think you are good.

My experience with a 560 gtx factory oc sli set up is that SLI in general seems to run fine. I'm using the latest WHQL drivers (so the ones from October, just before Skyrim came out), which are probably about 20% slower than using the current beta (based on nvidia's claims for 290.53+).

Running at 1920x1080, and vsync on, when framerates are at 60fps (which is most of the time) the game is very smooth. Usually the gpus are not stressed at 60fps, and nor is the cpu (oc'd 2600k @4.6Ghz).

There are three types of exception I'm seeing to smoothness:

i. cpu bound - e.g. Markarth. In these cases, after the 1.4 patch, the game is smooth even at lower fps (lowest I've seen is around 45-50), with a very slight stutter which I think is purely timing of frames vs. the 1/60th second vsync 'slots' for a frame to be displayed

ii. gpu bound - this one is odd, but there are some indoor locations that send the gpu load to 100%. In these cases, the framerate drops to around 48fps or so (which in theory would go back to 60fps for me once nvidia releases some new WHQL drivers, as I don't want to use their beta drivers at the moment due to TDR issues with some set ups). These areas tend to be noticeably stuttery, but I really have no idea why the gpus are being worked so hard. SLI scaling in these spots is pretty much 200%, i.e. if i switch off sli, the fps halves to around 24.

iii. 64hz stutter - this one happens in some indoor areas where the fps is locked at 60, and neither gpu nor cpu appear to be at 100%. I assume this is the gamebryo bug. The stutter is noticeable if you're looking for it, but not too bad if theres a lot of stuff going on and you're not actively concentrating on it

Basically, I'm not seeing classical SLI based microstutter, except possibly in those odd gpu bound internal areas. I suspect that once I get onto the higher performance drivers, microstutter will either go away or be minimal.

VRAM is definitely an issue: 1Gb is enough for the the high def texture pack at 1920 x 1080 (running at 2xAA, 16xAF, and 2xSSAA), but I can't run the full fat version of the various HD mods on the nexus, and nor can I run 8192 shadow resolution in interiors.

If going down the SLI route, I think the 560 gtx card is more than sufficient for good skyrim performance. If going down the single card route, I'd be tempted to go with the 580 gtx if budget is not an issue, simply because there are places that seem to stress gpus (although in fairness, these are isolated spots). Based on the fact that I'm seeing 100% gpu usage in those spots, and full SLI scaling, my assumption would be that the 580 gtx would deliver probably about 10 fps less than the SLI'd 560 gtx set up.

NVIDIA (lol read my sig)
Far from dislike my card
Highly dislike AMD Drivers etc.