AMD HD 7990 Review; Malta Arrives

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Temperatures & Acoustics / Power Consumption

Temperature Analysis

For all temperature testing, the cards were placed on an open test bench with a single 120mm 1200RPM fan placed ~8” away from the heatsink. The ambient temperature was kept at a constant 22°C (+/- 0.5°C). If the ambient temperatures rose above 23°C at any time throughout the test, all benchmarking was stopped..

For Idle tests, we let the system idle at the Windows 7 desktop for 15 minutes and recorded the peak temperature.

The high end cooling solution installed by AMD onto this card is nothing short of spectacular. It may dump loads of hot air into your case but the three large fans and extensive heatsink keep temperatures well under control.

Acoustical Testing

What you see below are the baseline idle dB(A) results attained for a relatively quiet open-case system (specs are in the Methodology section) sans GPU along with the attained results for each individual card in idle and load scenarios. The meter we use has been calibrated and is placed at seated ear-level exactly 12” away from the GPU’s fan. For the load scenarios, a loop of Unigine Valley is used in order to generate a constant load on the GPU(s) over the course of 15 minutes.

AMD claims the HD 7990 is one of the quietest cards currently available and if fan noise was the only factor in this equation, it would easily outpace competing solutions in this regard.

Unfortunately, coil whine drove our sample’s acoustical profile into annoying levels. In applications where the HD 7990 displayed high framerates it wailed like a banshee and lower performance situations caused it to exhibit an odd “chugging” noise. This proved to be immensely distracting, regardless of how quiet its fans are.

System Power Consumption

For this test we hooked up our power supply to a UPM power meter that will log the power consumption of the whole system twice every second. In order to stress the GPU as much as possible we used 15 minutes of Unigine Valley running on a loop while letting the card sit at a stable Windows desktop for 15 minutes to determine the peak idle power consumption.

Please note that after extensive testing, we have found that simply plugging in a power meter to a wall outlet or UPS will NOT give you accurate power consumption numbers due to slight changes in the input voltage. Thus we use a Tripp-Lite 1800W line conditioner between the 120V outlet and the power meter.

Shoe-horning two HD 7970 cores onto a single PCB naturally results in some impressively high power consumption numbers. However, due to lower voltages, reduced clock speeds and an efficient cooling system, the HD 7990 requires much less power than a pair of HD 7970 GHz Edition cards. Compared against the GTX 690 however, AMD’s flagship is a porker when under load.

Luckily, it looks like ZeroCore Power is making its presence felt here as the idle power consumption numbers are phenomenal.

 

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Overclocking Results

Overclocking Results

Currently, the only way to overclock an HD 7990 is to use AMD’s Overdrive utility and the strict limitations that it comes with. A 100MHz core overclock and a just 300MHz of memory overhead didn’t allow for substantially better performance but they did bring framerates closer to HD 7970 GHz Edition Crossfire territory. We're sure board partners will release software which allows for higher speeds.

AMD has also provided a slider to increase the card’s PowerTune limit. Upping this to the maximum +20% is an absolute necessity if you want to take advantage of higher clock speeds.

 

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Conclusion: Opportunity Missed

Conclusion

The HD 7990 cuts an imposing figure. It is a gargantuan card equipped with two Tahiti XT cores, delivering some impressive framerates and the massive heatsink ensures quiet operation, unlike the spectacularly loud dual GPU Radeons of yore. However, the HD 7990 is more than a year late so instead of being the undisputed champion of the graphics market, it has to contend with the likes of NVIDIA’s GTX 690.

As a flagship product, one can’t help but be impressed with what AMD has achieved here. Despite being saddled with an architecture that consumes copious amounts of power and pumps out a significant amount of heat, they were able to (finally) release a solution which can compete against the best NVIDIA has to offer. On paper that is.

The first chinks in the HD 7990’s armor are more than evident when playing some of today’s most popular games. Far Cry 3, Tomb Raider and Crysis 3 are just a few of the many titles which stutter along, lacking the relative fluidity provided by a GTX 690. Granted, the GTX 690 has a few minor hiccups of its own but this is an old problem for AMD and one which obviously persists to this day. A solution is supposed to be rolled out in the coming months (check out the Postscript page for a tantalizing look at what's in store) but AMD has been unable to provide an official release timeline, providing cold comfort to anyone who buys this $1000 graphics card right now.

Drivers don’t help this situation either with the HD 7990 lacking an Eyefinity profile for Assassin’s Creed III while the profile for Far Cry 3 is thoroughly broken with an out-of-wack HUD marring the experience. That’s a bit of an embarrassment for a card which is supposed to thrive in multi monitor environments.

So regardless of frame time issues and some minor driver hiccups, is the HD 7990 today’s fastest graphics card in terms of raw rendering speed? FRAPS certainly thinks so but there’s more to this review than just a narrowly focused story told by software solutions. When looking at the actual on-screen framerates, the HD 7990’s tendency to either drop or partially render frames leads to reduced onscreen performance in nearly every title. The end result is slower performance than a GTX 690 in this key metric.

Make no mistake about it, the HD 7990 is a great card which will likely have a bright future (provided AMD gets a handle on frame delivery at some point) but right now, NVIDIA’s GTX 690 is superior in almost every conceivable way. It provides smoother gameplay, more consistent framerates and lower power consumption without costing a dime more or exhibiting the HD 7990’s tendency for distracting amounts of coil whine. AMD does however hold a serious edge in the value-added department with their inclusion of eight free games. Indeed, when we look at the HD 7990, we see unrealized potential above all else.

If anything, we’re confused as to why AMD felt they had to release this card right now. A fix for the HD 7000 series’ frame latency headaches is just over the horizon, potentially negating many of the subpar results we saw. In addition, AMD’s board partners have already introduced a relatively successful batch of HD 7990 cards in the form of ASUS’ expensive ARES and PowerColor’s $899 Devil 13.

There was an opportunity here to have board partners continue with their own dual GPU cards while striving to make the “reference” HD 7990 a poster child for improved onscreen fluidity and consistent frame delivery. That didn’t happen. Instead, we have a high priced graphics card which highlights AMD’s faults without bringing anything particularly new to the table. It's like AMD is saying "buy this now and we'll give you some great results....soon."

Considering the original dual HD 7970 New Zealand card was supposed to have been released in early 2012, AMD would have truly benefited by keeping this new Malta product in the oven for just a bit longer. If you don't believe us, look no further than what their Frame Pacing prototype driver brings to the table.

 

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Postscript: AMD’s Frame Pacing Driver Benchmarked

Postscript: AMD’s Frame Pacing Driver Benchmarked

Only a few hours before this review went live, we were told that AMD had something special for us. Well aware of their issues with frame times, and dropped / partially rendered frames, the Catalyst driver team has been hard at work, developing what they call a “Frame Pacing Driver” which is supposed to monitor frame production more accurately in order to reduce stutter and essentially increase onscreen performance. Lo and behold, waiting in our inbox was an early alpha stage driver which is one of the first steps in a lengthy process towards making this goal a reality.

Before we go on, there’s a few things that have to be laid out on the table. First and foremost, this is a prototype driver and as such, it is not meant for public consumption as there are a number of significant bugs that still have to be ironed out. In addition, AMD isn’t giving any firm timeline for the inclusion of so-called “frame pacing” into their beta drivers.

So let’s see what the alchemists in AMD’s driver team have been up to.

First up we have Crysis 3 and the effect of this new driver is simply stunning. Prototype it may be but the onscreen framerate increase is impressive and the amount of stutter has been drastically reduced. If anything, we would now term the overall experience buttery smooth.

There really is a lot to like here considering the stuttering mess Crysis 3 is with the launch drivers.

Tomb Raider shows very much the same positive impact as within Crysis 3. Stutter has been drastically reduced and the number of partially rendered / dropped frames has been reduced significantly. While stutter hasn’t been completely eliminated, this leads to better framerates.

Unfortunately we had to stop benchmarking there since a few hours with the driver didn’t allow for much more but this should give you a tantalizing glimpse into what AMD has in store.

Now, this doesn’t change our conclusion one bit since the HD 7990 will still be launched with the 13.5 betas which were used in all of the other benchmarks within this review. AMD isn’t anywhere close to releasing this driver to the public so buyers of the HD 7990 will likely face weeks if not months of reduced performance and stuttering. This card is simply a missed opportunity to truly showcase what will become a major boost for all HD 7000-series users. But if the results above are any indication, the HD 7990 could very well become the fastest graphics card on the planet. It will just have to wait a while to get there.