post #61 of 61
The funny thing is that in all their previous reviews [H] and kyle always say that CFX does not feel as smooth as SLI. The thing is that in that conclusion they're not actually talking about smoothness or anything. What they're referring to is being able to run certain in game settings at a certain fps. This is due to their testing methodology.

The differences between [H]'s 7970CFX and 7990 come from clocks btw. 7990 is horrible at maintaining advertised clocks.

Read any of their SLI vs. CFX reviews, they always say SLI feels smoother. And they've done this even before frame times started appearing in reviews so it's not like they're just saying it because it's trendy.

This is something pretty much every review said about the 7990:

TechSpot Warning: Spoiler! (Click to show)
Quote:
Up until that point, it smelled like roses for the Radeon HD 7990. However move to the frame time data and things get a little more complicated and a lot less promising for AMD’s new dual-GPU flagship.

Against the GeForce GTX 690, the Radeon HD 7990 was 15% slower (where it was 7% faster before). The HD 7990 was also 9% slower than the GTX Titan, and a mere 25% faster than the GTX 680. There were just two games where the Radeon HD 7990 offered better frame time performance than the GeForce GTX 690: Hitman Absolution and Sleeping Dogs, while coming close in Medal of Honor, Max Payne 3 and DiRT 3.

After much talk over frames per second vs. other metrics that more closely represent what users see on-screen, particularly when using multi-GPU setups, we have become wary of recommending them.

Looking at the figures in this review, it's hard to recommend Crossfire technology over SLI, and then SLI over a single high-end GPU. Though we acknowledge that AMD has been making great strides in improving frame latency, they are not there yet. We suspect this is part of the explanation why the Radeon HD 7990 was held off for a few months in the first place.

BitTech (doesn't include Frame-times..but) Warning: Spoiler! (Click to show)
Quote:
We must admit to being a bit disappointed by AMD's current lock-down of the 7990's overclocking abilities. With the release driver, we were only able to increase the core frequency by 10 per cent to 1,100MHz, bumping the card's power threshold by 10 per cent to accommodate. Perhaps more surprisingly, this had a minimal impact on in-game performance in both Unigine and BF3. The Unigine score improved just 6 points to 2177, still some way off the 2442 we managed using a pair of 7970 1GHz Edition in CrossFire, while the minimum frame rate in BF3 also rose only moderately, increasing by four per cent to 76fps at 2,560 x 1,600 with 4x AA. Whether it's power threshold throttling, poorly optimised drivers or an in-efficient PCB design, even overclocked the HD 7990 3GB isn't as quick as a pair of 7970 GHz Editions in CrossFire.
Quote:
Most importantly though, there's the matter of pricing and value. When Nvidia launched the GTX 690 4GB last year we were shocked at its £850 price tag; a £50 premium over a pair of GTX 680s at the time. Given the fact that a board-partner's HD 7990 6GB was actively available for around £700 last year, we were honestly expecting the official HD 7990 6GB to cost roughly the same. The fact that it instead costs £860, £200 more than a pair of HD 7970 3GB GHz Editions, can only be seen as a disappointment, even with the impressive technical accomplishments involved in squeezing two GPUs onto a single PCB and requiring only a pair of 8-pin power connectors. Looking at our Unigine points/£ graph its right down in Titan territory in terms of poor value, without offering the advantages inherent in a super-powerful single GPU. Meanwhile the GTX 690 4GB has now slipped to under £800.

HotHardware Warning: Spoiler! (Click to show)
Quote:
There are a number of points related to the Radeon HD 7990’s performance we should discuss in this summary—frame rates, frame latency, power consumption, and noise. As the results on the preceding pages have shown, the Radeon HD 7990 puts up some impressive frame rates, outpacing the similarly priced GeForce GTX 690 and GTX Titan more often than not. Those frames, however, are not always delivered to the screen in a consistent, fluid fashion, which can result in stuttering or interruption of motion that can detract from the overall experience. The card is rendering the frames, but they’re not being sent out to the display at regular intervals. Some frames are displayed correctly, while others are dropped or only displayed for a few scan lines.

These frame latency issue are a shortcoming of AMD’s current CrossFire implementation, and the company is currently working on a fix. We actually received a prototype driver yesterday (which unfortunately came in too late to test) that reportedly addresses some of the issues, but they won’t be fully optimized and released to the public until sometime this summer. From talking with AMD (and NVIDIA), we believe AMD is going to be able to resolve the frame latency issues with CrossFire setups, but it’s unclear at what cost. Performance may ultimately be impacted, but we won’t know for sure until the drivers drop in a few months.

Anantech (no frame results..but) Warning: Spoiler! (Click to show)
Quote:
However that brings up a second point: if the GTX 690 and 7990 are equal in performance, are they equal overall? No, and that’s for two reasons. The GTX 690 is a 300W card and the 7990 is a 375W card. The GTX 690 consumes around 75W less power and puts off 75W less heat, full stop. From a power/performance perspective, that scenario makes the GTX 690 look like the better card. It’s very reminiscent of what we’ve already seen with GK104 vs. Tahiti in single-GPU cards; NVIDIA has AMD beat on power efficiency right now. Power consumption isn't everything, mind you, but there is a notable difference.
Quote:
Speaking of the GTX 690, this brings up our other concern: timing. There’s really not a very good way to point this out, but AMD’s 7990 is historically late. AMD usually ships their dual-GPU capstone part no more than 6 months after the launch of a new family, and instead it will have been 17 months after the launch of the first 7970 by the time the first AMD 7990 ships. That’s just shy of a year after the GTX 690, the card AMD is just tying today.

PC Perspective Warning: Spoiler! (Click to show)
Quote:
Perhaps they are using multiple displays for Eyefinity/Surround setups - in that case, the HD 7990 has different but equally traumatic problems. In our testing, nearly every other frame generated by all of our games tested are dropped and never shown to the gamer, resulting in frame rates at about half of what they should be and half of what is being reported by some other testing methods. That's just not acceptable. We are working on another story that directly compares the issues of Eyefinity and Surround that we hope to have up by next week along with some videos to demonstrate those complicated issues.
Quote:
But we can't really assume that today... So how does it compare to the GTX 690 or the GTX Titan? Honestly if you are going to spend $999 on a graphics cards you should really be deciding between the GTX 690 and the GTX Titan. I would go the route of the Titan and its single GPU + 6GB frame buffer for multi-monitor setups and the GTX 690 for single, high resolution monitor users.

TechPowerUP Warning: Spoiler! (Click to show)
Quote:
Finally! AMD's Radeon HD 7990 is here! We've been anticipating the release of this card since the HD 7900 Series was introduced, and since NVIDIA released their GeForce GTX 690 flagship almost a year ago. The company's new card is built on the foundation of two full-fledged Tahiti GPUs that come with all shaders unlocked. Both also run at up to 1000 MHz, which almost matches the clock speeds of the HD 7970 GHz Edition. Our performance testing reveals excellent performance results in games where CrossFire is working as intended, making HD 7990 the fastest graphics card in the world in these cases. Recent titles like Crysis 3, Tomb Raider, and Bioshock Infinite show good scaling that easily surpasses the performance of competing cards, like the GTX 690 and GTX Titan. However, we've also seen many games that do not scale well, and they make up a significant portion of our tests. Out of eighteen titles, five did not scale, or worse, showed negative scaling. These are not small titles, but big AAA games: Assassin's Creed 3, Batman: Arkham City, F1 2012, StarCraft II, Skyrim, and World of Warcraft. What really surprises me is that this long list is the same as the one we had with our reviews of HD 7990 "New Zealand" implementations by board partners, like the ASUS ROG ARES II and PowerColor Devil 13. So either AMD does not care or can't fix CrossFire support with these games millions of people play.
Quote:
To look at things from a different perspective, we created a second set of performance summary graphs that excluded all these problematic games, representing a scenario better suited to CrossFire usage, but the HD 7990 still only managed to beat the GTX 690 by 6% at 2560x1600, which is hardly a convincing result with the scaling issues looming in the background. Some people might argue that we could see better CrossFire scaling in the future because AMD graphics technology will power all future consoles, but I'm not so sure about that. Console developers don't develop for CrossFire and are happy that they only have to support a single hardware configuration.

TomsHardware Warning: Spoiler! (Click to show)
Quote:
AMD wants $1,000 for this new flagship—the same price as GeForce GTX 690, which yields a higher practical average frame rate in six of our eight benchmarks as it delivers frames more smoothly across the board. The GTX 690 is shorter, set up to exhaust at least some of its waste heat out of your chassis, and significantly more power-friendly. It eschews plastic in favor of metal. And it doesn’t whine under variable loads. Nvidia simply sells a better-built dual-GPU graphics card.
Quote:
But when we combine the quantitative data enabled by video capture-based performance analysis and the subjective judgments of a panel of gaming enthusiasts who simply want to play their favorite titles on the best hardware possible, Nvidia’s thousand-dollar GeForce GTX 690 outshines the similarly-priced Radeon HD 7990. Our early look at AMD’s prototype driver suggests that more evenly pacing the rate at which frames are shown on-screen helps minimize frame time variance, which our gamers definitely noticed. But that release isn’t expected for months—the second half of 2013 is as specific as AMD gets.
And so we’re faced with a card that represents a huge improvement over its predecessor, but still comes up shy of its competition, and is priced like an equal.
Quote:
I set two open test beds behind a pair of Auria EQ276W 27” displays. The systems were both running Z77-based motherboards with Ivy Bridge-based Core i7 processors and 16 GB of DDR3-1600 memory. Both featured 256 GB SSDs with identical drive images, too. The test subjects weren’t told which system had which card, or to which test bed their monitor was attached. Though, over the course of seven hours, I did let them know where their opinions were leading us. Each gamer spent between 10 and 15 minutes in front of each screen (I was only able to involve five folks for this; I’d like to at least double that in the future), before switching and repeating.

The Verdict

Unanimously, the entire group identified game play on Nvidia’s GeForce GTX 690 as the smoothest. Although I was worried about group pressures affecting the responses, or any of the other pitfalls associated with subjective analysis, each gamer was asked to identify the factors that affected his judgment, and we received specific answers.

And then there's the fact that the 7990 doesn't really OC at all. After I OC my Titan it's on par fps wise and it has more vram, better frame times, produces less heat, is less loud, and so on.

7990 is just a completely bad purchase. At the very least a person considering it for some OCL work or something should just get the powercolor model since it has a better PCB and it can actually OC and doesn't throttle to 950MHz half the time.

But hey lets recommend a card that all reviews say is sub-par just because of the brand. Honestly at this point 7870, 7950 and 7970 are great cards but once you go over that in price range you want to go with Nvidia.

Just look at this:


Or read about the blind test TH conducted: http://www.tomshardware.com/reviews/radeon-hd-7990-review-benchmark,3486-13.html

spoiler: every single person testing the card said the 7990 was not as smooth as a 690 which is less smooth than a Titan/780. And the funny thing is that all of this applies to the 7950CFX setup as well.
Edited by Alatar - 6/3/13 at 12:30am
 
Benching
(17 items)
 
 
CPUMotherboardGraphicsRAM
[i7 5960X @ 4.8GHz] [Rampage V Extreme] [Titan 1400MHz (1500MHz bench)] [Various] 
Hard DriveCoolingCoolingCooling
[250GB 840EVO +2x SpinpointF3 1TB RAID0] [LD PC-V2 SS Phase Change] [XSPC X2O 750 pump/res] [Monsta 360 full copper + EK XT 360 + XT 240] 
MonitorPowerCaseAudio
[Crossover 27Q LED-P 1440p+ASUS 1200p+LG 1080p] [Corsair AX1200] [Dimastech Easy v3.0] [Sennheiser HD558s] 
CPUCPUMotherboardGraphics
FX 8320, FX 8350, Phenom II x2 555BE i7 3930K, i7 860, i7 4770K, 68x Celeron D CVF, commando, 2x RIVE, Z87X-OC Asus 4870x2, Sapphire 4870 
GraphicsGraphicsGraphicsGraphics
2x 5870, 5850, 5830, 5770 2x 3870x2, 3870 GTX Titan, GTX 480, GTX 590 GTX 285, GTX 260, 4x 9800GT, 8800GTX 
RAMHard DriveCoolingCooling
4x4GB vengeance, 2x4GB predatorX, 2x1GB OCZ DDR2 Intel X25-M 80GB LD PC-V2 SS Phase Change OCN Marksman 
CoolingCoolingOSPower
2x old tek slims (GPU) Various watercooling stuff win7, winxp AX1200 
Case
test bench / cardboard box 
  hide details  
Reply
 
Benching
(17 items)
 
 
CPUMotherboardGraphicsRAM
[i7 5960X @ 4.8GHz] [Rampage V Extreme] [Titan 1400MHz (1500MHz bench)] [Various] 
Hard DriveCoolingCoolingCooling
[250GB 840EVO +2x SpinpointF3 1TB RAID0] [LD PC-V2 SS Phase Change] [XSPC X2O 750 pump/res] [Monsta 360 full copper + EK XT 360 + XT 240] 
MonitorPowerCaseAudio
[Crossover 27Q LED-P 1440p+ASUS 1200p+LG 1080p] [Corsair AX1200] [Dimastech Easy v3.0] [Sennheiser HD558s] 
CPUCPUMotherboardGraphics
FX 8320, FX 8350, Phenom II x2 555BE i7 3930K, i7 860, i7 4770K, 68x Celeron D CVF, commando, 2x RIVE, Z87X-OC Asus 4870x2, Sapphire 4870 
GraphicsGraphicsGraphicsGraphics
2x 5870, 5850, 5830, 5770 2x 3870x2, 3870 GTX Titan, GTX 480, GTX 590 GTX 285, GTX 260, 4x 9800GT, 8800GTX 
RAMHard DriveCoolingCooling
4x4GB vengeance, 2x4GB predatorX, 2x1GB OCZ DDR2 Intel X25-M 80GB LD PC-V2 SS Phase Change OCN Marksman 
CoolingCoolingOSPower
2x old tek slims (GPU) Various watercooling stuff win7, winxp AX1200 
Case
test bench / cardboard box 
  hide details  
Reply