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Oops, hehe. No SLI was used for my scores. When I wrote x2 PCI-E what I meant was one single card in the second PCI-E slot, which was set to 2x, and x16 PCI-E meant the top slot running at 16x. Sorry, I should have been clearer. So to sum it all up: 1) I own a single eVGA 7800 GT CO and have been using it with my DFI SLI-DR motherboard since early winter of 2005. I use it in the second PCI-E slot to keep heat off my NF4 chipset, and thus the graphic card is running at x2 (times two) speed. Other folks here at DFI Street have shown that running at x2 in the second PCI-E slot instead of x16 in the primary PCI-E slot has little to no impact on 3D performance. 2) I decided to spend the big bucks and buy two BFG 7900 GTX OC cards on August 6, 2006. Since I like to run all my PC games at 1920x1200 with 4xAA and 16xAF whenever possible (due to owning a Dell 2405FPW LCD monitor) all I was really after was a bit more performance, double preferably though more is always nice . From my research, two 7900 GTX cards running in SLI looked a bit better performance-wise than one 7950 GX2, and so is why I went that route to begin with. 3) Several days after installing my two new BFG 7900 GTX OC cards they began to act very buggy. This happened whether they were running alone in either of the two slots, or in SLI mode with both installed. Research showed that a lot of people seem to be having the same kinds of problems. I was unable to complete any benchmarks without encountering major issues myself, such as all the points listed in the first post of this thread, and this is why I don't have any 7900 GTX based numbers included in my previous benchmarks post. As I posted a while back in this thread, I did manage to complete one run of 3dMark05 in SLI mode with the two BFG 7900GTX's while running two power supplies, but this was a lucky fluke more than anything and the score was over 1600 marks lower than what my single 7800 GT generally scores, proving once again that something was seriously wrong with them BFG's. 3) NCIX, the store I purchased both BFG 7900 GTX's from, agreed to take the faulty cards back on August 17, 2006, provided everything was still together and in mint condition. They said they would give me a single eVGA 7950 GX2 card in exchange as well as a refund of the difference, and I was perfectly happy with that. They recieved my RMA return on August 25, 2006, and on September 8, 2006 my brand spanking new eVGA 7950 GX2 arrived. 4) Performace of this single eVGA 7950 GX2 is exactly what I was hoping for over the single eVGA 7800 GT CO it's replacing. All I have to solve now is the heat issues, though even as hot as it gets sometimes (90c and up) I've yet to see any visual anomolies or bad behaviour, unlike my eVGA 7800 GT CO which shows really bad texture flashing between 75c to 80c. I noticed the point at which the 7950 GX2 throttles back it's clock speeds to prevent damage to the core is a bit higher than the 7800 GT (122c vs 105c if I recall correctly), so it looks like it may be designed with a bit more heat in mind. There is a vent on the rear of the card, but sadly the open design of the fan and heatsink assembly don't really force hot air out that way. The only problems I encoutered when installing my 7950 GX2 that others might be interested to hear: A) One of the support posts that hold the two cards together had to be removed. This was only needed because it would hit my SATA ports, all of which are in use on my particular motherboard. The screws are pretty small, but it was easy to do. B) Had to change my DVI cable from one head to the other. The one closest to the motherboard wouldn't allow the BIOS to post for some reason. C) I also had some trouble getting the card to sit flush in it's PCI-E slot too, so this might have played a role in the POST difficulties above as well. Fix involved using pliers to bend the metal bracket on the graphics card upwards a bit. Part of this is my Cooler Master case, which are known to cause problems with PCI card installations. D) Can't use the second 2x slot anymore. The 7950 GX2 must go into the top most x16 slot. The card will work in the second slot, but not in dual GPU mode. E) Forced to use the new 9-series Forceware drivers, which are probably going to be buggy for a while yet. Looking at the 91.47 documentation, it appears that Nvidia is at least aware of the worst of it now, so hopefully it won't take them too long to fix. Can't say I like the design though, which neither looks nice nor is intuative, the whole reason why Nvidia changed them all around I believe. And that's my whole story pretty much. I think I'll be happy with the 7950 GX2 for at least a year. At some point a DirectX 10 card is going to become a neccesity I'm sure, just like nine eventually did, but my plan is to hold off for as long as possible... hence why I'm upgrading now instead of simply waiting. I don't really want a first gen DX10 card if it can be helped.

I finally got my eVGA 7950 GX2 yesterday. Had to remove one of the posts so it would fit onto my motherboard, but that wasn't a big deal. Peformance is double over my eVGA 7800 GT CO at the setting I prefer (1920x1200 with AA & AF on). The only problem I'm forseeing here is how hot this card gets. It hit 96C while playing FEAR for a few minutes, and idles at 69/56 celcius. I only have air cooling, but even so it's usually pretty decent most of the time with the case. Looking in the 91.47 drivers it looks like 122c is the point at which it throttles back, so I'm hoping the thing was designed with this high level of heat in mind. If so then I'm happy, and if not then I'm worried lol. Anyways, here are some benchmarks if anyone is curious. ;-) Edit: Neither situation is SLI. Sorry for any confusion I may have caused. eVGA 7800GT CO (In second slot @ x2 PCI-E) No Overclocking Forceware v84.21 (High Quality) 3DMark05 (Default Run @ 1024x768) Score: 6771 GT1 - 30.9 fps GT2 - 19.1 fps GT3 - 33.7 fps CPU Score: 3952 CPU Test 1: 1.9 fps CPU Test 2: 3.6 fps 3DMark05 (1920x1200 / 4xAA / 16xAF) Score: 2763 GT1 - 13.8 fps GT2 - 5.5 fps GT3 - 17.8 fps 3DMark06 Score: 3665 SM2.0 Score: 1478 HDR/SM3.0 Score: 1399 CPU Score: 1642 Counter Strike Source 1920 x 1200 Maxed Settings 4x AA / 16x AF 55.27 fps F.E.A.R. (v1.06) 1920 x 1200 4x AA / 16x AF Maxed Settings No Soft Shadows Minimum: 14 fps Average: 24 fps Maximum: 52 fps 72% below 25 fps. 16% from 25-40 fps. 12% above 40 fps. -------------------- eVGA 7950 GX2 (In first slot @ x16 PCI-E) No Overclocking Forceware v91.47 (High Quality) 3DMark05 (Default Run @ 1024x768) Score: 12592 GT1 - 47.9 fps GT2 - 37.8 fps GT3 - 70.6 fps CPU Score: 6722 CPU Test 1: 2.9 fps CPU Test 2: 7.0 fps 3DMark05 (1920x1200 / 4xAA / 16xAF) Score: 6608 GT1 - 34.5 fps GT2 - 14.2 fps GT3 - 37.7 fps 3DMark06 Score: 7631 SM2.0 Score: 3510 HDR/SM3.0 Score: 3378 CPU Score: 1856 Counter Strike Source 1920 x 1200 Maxed Settings 4x AA / 16x AF 158.33 fps F.E.A.R. (v1.06) 1920 x 1200 4x AA / 16x AF Maxed Settings No Soft Shadows Minimum: 32 fps Average: 54 fps Maximum: 135 fps 0% below 25 fps. 25% from 25-40 fps. 75% above 40 fps.

Mind giving a description of the artifacts? Some types of artifacting can clearly point to video memory, and some to the GPU itself, especially when overclocking is involved. If you're not experiencing all of the points listed in ths first post of this thread, then it is possible that you may not be having the same problem as all the others who do. When it strikes, it seems to be permanent for the most part and not a whole lot helps, especially when it comes to the Deep Freeze test in 3DMark06. For example, you said that turning down the clock speeds of the core and memory helped mitigate some of the artifacting you were getting and that 3DMark06 ran smoothly again, which based on my travels is something I haven't really seen work for anyone having the full gamut of listed issues. This means you could be experiencing a different problem entirely I suppose. What are your temperatures (core, ambient, and memory if you're able)? Overheating would be my first suspect considering the description you gave. I've found with my eVGA 7800GT CO, which is factory overclocked, that depending on the game, it can start artifacting as low as 65C on the GPU. Usually it shows up as textures flashing. More often symptoms like this don't show up until 70C and higher, but like I said, what 3D software that is running definitely seems to play a part. It's annoying too since, as far as I know, there is no built-in mechanism on Nvidia cards to read what the memory temperature is, and only some cards can read ambient temps. I have a theory that memory temps might help explain why artifacting shows up under the circumstances that I've just described, but I will likely never really know. That is, unless I buy a good temperature probe of course, but I have no plans to do so anytime soon since it's not super important (annoying yes, but doesn't cause any problems) and the card is being replaced soon anyways. But I digress. To wrap up my rather long-winded post, a clearer description of all the issues you've been seeing, your temperatures, and exactly what kind of artifacting you are seeing will help a lot for folks trying to help you out. Take care, and hopefully with a little luck you'll be able to avoid going through an annoying RMA process.

One can only hope. Of course, if a power supply was going to destroy everything in rig, it will not have mattered which one I was using. That's the kind of luck I have lol.

Same reason I try to seek as much power as possible when I can afford it. I mean, my Dell looks alright as long as the resolution doesn't drop below 1280x1024, provided of course that the game doesn't use models and textures that are too low in poly and pixel counts. Amazingly, even some newer games still limit the maximum resolution you can run at, like Dungeon Siege II for example. Anyways, provided the game allows it, I much prefer to game at my monitors native resolution of 1920x1200 whenever I can, even if it means an occasional framerate drop here and there. Games look amazing; add in 4xAA and 16xAF and I'm just happy as a clam hehe. I certainly hope you're as happy with your new monitor and card when you get them.

Wow, I highly doubt that this statement is true, though I'm sure it might be some day if you manage to successfully get everyone using an OCZ GameXStream and nothing else lol. Perhaps both DFI and DFI-Steet could add it to their terms of service as a written in stone requirement. Use only OCZ power supplies OR ELSE lol! Would certainly make life easier for those trying to help out users of DFI products if everone were to use exactly the same gear, and also make OCZ extremely happy as well. I certainly hope you're getting paid - or at least getting free gifts if not - for all your free advertising and powers of persuasion. After all, you clearly deserve something in return for huge amount of effort you've personally put into this project. Haha, I'm just joking with ya; couldn't resist. If my Aerocool were to break down any time soon (which it inevitably must since it's on this list) I'll very likely buy an OCZ GameXStream to replace it. I have nothing against OCZ, and own some of their memory which, in the past, has had to be replaced due to being faulty. I really can't think of anyone better when it comes to product support; they are the best IMHO. Like I said in my previous message, if the power supplies they were selling at the time I needed one had met my needs exactly, it's what would be in my PC right now instead of the Aerocool.

This list is far too generalized, and does folks a disservice. I'm certain that most of the manufacturers on this particular list are perfectly capable of making at least one good power supply. I mean, is it really possible for any manufacturer to design and build a junk power supply every single time? How about vice versa? Do the manufacturers that build what people consider to be good supplies have a 100% success rate with every new model they release? Hopefully folks see what I'm getting at. This list is much better since it is much more specific, though I'm not sure that it is 100% impartial. Please don't take that, or this post, as an attack as it's not. Just take it at face value. The wisest thing people should really be doing is to read as many reviews as they can get their hands on, as well as try to find comments by people that actually own the specific power supply they are interested in buying. The best performing power supply in the world doesn't mean a thing if it doesn't meet all of a persons needs, like noise, physicial parameters such as dimensions and cables, and so on, and everyone is definitely going to be different in that regard. It's why I myself didn't end up with an OCZ back when I was trying to find just the right one for my needs; the GameXStream didn't exist at the time, although I hear it's kind of noisy so I may still not have purchased one had it been available. What can I say, I'm picky lol. FWIW, I'm still perfectly happy with my Aerocool 620W ZeroDBA. So far the only bad thing about it has been the short warranty period, but since I haven't had to make use of that, the warranty length really hasn't mattered all that much. Despite having a few negatives each that I dislike, the Enermax 600W Noisetaker and Ultra X2 550W power supplies are both still going strong too... and I still refuse to ever buy another Antec until they clearly improve. The brand may be considered good by a lot of folks, but their quality control definitely isn't lol.

Hmm, underclocking the memory didn't help in my case, and I'm sure that I am not the only one who has tried this. I mean, if it were simply a matter of clock speeds being too high, then the problem would easily be remidied for everyone, would it not? I have no doubt that overclocking, possibly made worse by poor memory, is indeed part of the issue, but overall I think there is more to it and that this isn't the sole culprit. The one inescapable fact I know is that, if this were a simple problem to fix, we would have heard about it from someone by now, and everyone would be enjoying their 7900 series cards. Instead we keep hearing about people with RMA woes, where the replacements card(s) have the same problems as the one(s) sent back, in some cases more than once. In this, David is certainly not alone.

The chances are definitely slim. People having these particular issues seem to run a fairly wide gamut when it comes to make and model of motherboard, and logically that points to something else as being the culprit. The only thing that is really the same among everyone having trouble is that they are all using a 7900 series graphics card, very often factory overclocked. Still, it would probably be prudent not to discount other possibilities entirely I suppose, such as the motherboard. After all, the trick with raising the PCI-E bus speed does indeed seem to work for a few people. Then again, it is also entirely possible that these particular folks were not actually experiencing the same problem as the rest of us, as described exactly in the first post of this thread. And, to be perfectly honest, I have indeed seen what looks to be a discrepancy amidst the assorted descriptions posted among the various tech forums out there. In any case, either this problem will eventually blow over and we'll never know what the problem truly was, or the industry (Nvidia in particular) willl have no choice but to finally come forward and admit once and for all that there is a serious design flaw with the 7900 series. One way or another, it really would certainly be nice if this problem could finally be laid to rest once and for all, that is for sure. Regardless, I can't really complain anymore since things very much look like they are going to work out for me in the end. I mean, so I only get a 100% boost to games performace instead of 120%. Nope, that's really not such a big deal at all hehe.

I'll be happy to post some benchmarks when I get my 7950 GX2. While I do have nmbers from my 7800GT to share, I won't be able to give you any 7900GTX numbers based on my rig though since neither card would work properly, whether in an SLI configuration, or each solo. The only single time in which I managed to get one of them to finish a run of 3DMark05 was when I was experimenting with using two power supplies; an Enermax 600W Noisetaker to supplement my Aerocool 620W ZeroDBA (both good supplies from my experience). The score for a single BFG 7900GTX OC came out about a little over 1600 marks lower than the score for my one eVGA 7800GT CO, proving something is clearly wrong, probably having to do with the video memory as many whom have the exact same issues listed in the first post tend to suggest. And before someone points out that this may point at my power supply being the culprit, rest assured that it isn't the reason for my troubles as I thoroughly tested this hypothesis, which was my very first and before I found this thread. This included changing the load balance which didn't help either sadly. Too bad, actually, since this would have been a lot easier to fix lol. Anyways, if you're interested I did find this really good thread while looking up quad-sli recently, where another DFI Street member posted his experiences with an eVGA 7950 GX2 on nearly the same rig as I have (same motherboard, nearly the same monitor). Lucky I found it actually as I almost made the mistake of paying a bit more to try out quad-sli, which clearly would not have worked. Whew! David, I feel for you man. I wholeheartedly agree with what OldGuy said; that it sounds like they aren't testing the cards they send out as RMA replacements before hand to make sure they work 100%. However, I'm not entirely sure this would be completely effective. About half the folks I've seen on the various tech forums complaining about the issues that all brands of 7900 series cards are having don't always know there is something wrong right away. The cards can work for a couple of days before breaking down suddenly, and in some cases they may work fine for up to a week. I still think, like most, that it has something to do with video memory perhaps, but this might point to heat as being part of the cause as well. There is a poster named 'Cheetah gamer' in the Nvidia forums, for example, who claims that there are two IC's on the 7900 series which do not have any kind of passive/active cooling at all, are related to the video memory, and get hot enough to burn a persons finger. I think I read about it in this thread (yup, see post #37). It is regrettable in some small way that I am not getting two new 7900GTX cards to play with, as I have some copper sinks perfect for the job, and that I would have attached before using the cards for the first time. Might be worth trying when and if you get another RMA'd card. Certainly can't hurt to try anyways.

Thank you kindly good sir. Looks like I'm going to come out on top after all. I still get a great performance boost, plus the difference refunded which is around $500. Nope, not bad at all (thank goodness).

NCIX has officially approved my RMA exchange this afternoon. My two BFG 7900GTX OC's for one eVGA 7950 GX2 plus a refund of the difference in price. However, after coming across a post earlier today in the Nvidia forums where a user discovered his ASUS board doesn't support the 7950 GX2 (as told to him by an ASUS engineer), I realized that I don't actually know whether my DFI motherboard supports the 7950 GX2 either, and that I had better find out quick before agreeing to the exchange lol. I'm hoping someone here could let me know, or point me to a list if there is one. Thanks in advance everyone!

The vast majority of posts I've seen around the net on various tech forums always speak highly of eVGA equipment and their commitment to support. It's the primary reason why my last card was an eVGA, and had I known that his issue affected all of the 7900 series regardless of brand, I certainly would have prefered an eVGA over BFG myself. This is why I decided to ask NCIX for help first, that way I might perhaps be able to switch to an eVGA branded card instead, where as if I had gone to BFG I'd be stuck with them permanently. So far I've gotten what seems to be a positive reply from NCIX. They said I could trade in for a 7950 GX2 if I wanted, as long as everything I send back is in prime condition and I still have the original boxes and all accessories. They also asked me if I've tried updating my system BIOS, as well as the video card BIOS, but to be honest I really don't think doing either of those will help based on what I've read about the problem we are all having. I'm already running the newest BIOS available for my motherboard, which by the way helped me achieve better overclocks than the two previous versions I had been running (and thus don't want to give that up), and to the other, well I fear updating the BIOS on the video cards as that might void my warranty or make things worse should the update fail to take. I've read it can be a fairly dangerous procedure after all.

Thanks for the vote of confidence. I'm sure every person suffering from this problem could use some cheering up by now. I know I certainly needed it lol. At the last second I decided to fill out an RMA with NCIX instead of BFG, and ask them if a refund or exchange for a different card is doable. I have a VIP membership there, plus I paid extra for their express RMA option. I have experience dealing with them and they have always been pretty good about returns in the past. Certainly doesn't hurt to ask. I gave them plenty of links to look at to make sure they see it's a very common issue with the 7900 series. If it doesn't work out then I will talk to BFG and try to do the RMA thing with them instead I guess. You had a good point there about this not being a big secret, and I agree that it's very likely all the manufacturers are fully aware of the situation. Just have to be firm and hopefully things will all work out in the end.

I haven't contacted them yet regarding this problem, but the last time I had an issue, which was regarding s-video issues on a BFG 6800GT OC graphics card several months ago, they were very friendly and helpful. The tone of several recent posts by other DFI Street members has me a bit worried though. I sure hope that I'm not stuck with $1200 bookends. :sad: FWIW, I installed 3DMark06 and sure enough I have serious problems with the Deep Freeze tests, exactly the same as everyone else. So, I can check off ever single point on that list in the first post now. After some searching, I'm starting to see now that this problem with the Nvidia 7900 series actually affects a lot of people, and is regardless of brand. To be honest, I knew there were issues before I bought my cards last week, but I thought it was only eVGA ones that were having problems. This kind of sucks because it's why I went with BFG instead. I never would have spent that kind of cash if I had known that it's such a wide spread issue. The symptoms are exactly the same among everyone too (as listed in the first post) no matter where you go on the net. Clearly it's something specific to the 7900GT and 7900GTX hardware, whether factory overclocked or not. Like many others, I'm not really sure what to do. RMA them both now and hope I get newer cards that work properly, or wait until the problem is officially recognized by the industry and fixed, then RMA them. I can say this with absolute certaintly; the past week has been a complete nightmare. I am so worn out from trying every possible things I can think of to get them to work right, in SLI mode or solo. I am emotionally worn out, my fingers hurt from being cut so many times while working inside of my case, and am beginning to lose interest in PC's as a hobby I think. I've been starting to wonder that maybe I should just go back to my old ASUS P3B-F with a Pentium III 500, run Linux for the basics like surfing and e-mail, and just buy a nice console for all my gaming needs instead. I'm so sick of always having to troubleshoot PC related problems day after day. Everytime you fix one thing, something else takes it's place that you have to fix. It's a never ending cycle that's starting to drive me nuts. A console would be a hell of a lot cheaper in the long run too. Sigh... :sad: