Table of Contents
Flagship. It’s word that embodies everything that ASUS is trying to do with their HD 7970 DirectCU II TOP graphics card. Does it qualify for that title? Read on and let’s find out together!
Specifications & Features
Starting off with the specification list, you can see this card is made to be a strong competitor. It comes with a stock clocks of 1000 MHz on the GPU and 1400 MHz on the memory, 75 MHz and 25 MHz overclocks over reference, respectively. While that’s not a lot over stock, wait until you see how it’s made and what it can really do. Let’s just say ASUS was conservative when they stopped here.
In case you didn’t feel like reading the specifications, here is ASUS’ skinned version of GPUz for your viewing pleasure.
The features on this card are impressive too. As its name indicates, this card comes with ASUS’ DirectCU II cooling solution. This particular card’s cooler has six copper heatpipes, plenty of aluminum to dissipate the heat and two 100 mm fans supplying airflow.
20% cooler and 14dB quieter with exclusive DirectCU II thermal solution
One item more extreme overclockers will take advantage of is VGA HotWire. This allows you to hard-mod your card without having to actually do the work. They supply easy solder points for monitoring and controlling GPU, memory and PLL voltages. Hard-modding your card has never been so easy.
The catch is, to control these easily, you need an ASUS ROG board (Rampage IV Extreme or Maximus V Extreme). Thus, you’ll need to purchase a high-dollar board to go with your high-dollar card if you want to use this feature. Presumably you can find variable resistors and wire them to ground from the control points to use it without a ROG motherboard. Unfortunately I’ve yet to see data on this yet, so I posed the question to ASUS. They are checking with the product design team to see if they can obtain that info. The conversation was quite positive and they will hopefully be able to share the information. While GPU HotWire makes it convenient to use on their boards, they aren’t against allowing people to get the most out of their cards if they go with another motherboard choice.
Propreitary VGA hotwire allows you to plug and solder wires on the card’s voltage regulators and accurately read and control Vcore, Vmem, and PLL voltages from ASUS ROG MBs on a hardware level
For those of you that aren’t necessarily adept with a soldering iron, you do have ASUS’ GPU Tweak software that does allow GPU voltage control. GPU Tweak has clockspeed control, GPU voltage control, plenty of monitoring capability and even a ROG-skinned GPUz as you saw above.
GPU Tweak co-developed with the most authoritative GPU-Z to provide the most accurate information
The power section is one place where this card really separates itself. You’ll see more on it later in the review. Suffice to say it’s strong.
DIGI+ VRM with 12-phase Super Alloy Power
Acclaimed DIGI+ VRM with 12-phase Super Alloy Power technology Delivers precise Digital Power and Enhance Durability for stable overlocking
If you were paying attention, you already knew the card had 3 GB of GDDR5 memory and a 1000 MHz ‘stock’ clock.
Gigantic 3GB GDDR5 Memory
On-board memory for the best gaming experience & the best solution
1000 MHz Overclock
1000 MHz Overclock for better performance and outstanding gaming experience
The outputs on this card are definitely nonstandard, not that there really is much of a standard for non-reference PCB cards anyway. There’s something to be said for uniformity though and rather than four connectors with three different kinds of connector, with this card you get a whopping six connectors with only two kinds. All told you have two DVI ports and four DisplayPorts.
To those of you with DVI monitors that want to get more than two monitors using adapters, make sure you get active DisplayPort-to-DVI adapters. Passive adapters will not work. Active adapters cost about double what passive adapters cost, so be sure not to go cheap on the adapter.
Now let’s move on to the what’s-in-the-box section of our program.
Packaging & Accessories
The box for this card is good looking, as boxes go. If anyone ever played the N64 game Mace (seriously dating myself here), this character reminds me of Lord Deimos for some reason or another. Anyway, good looking box with lots of features outlined.
After opening the box, we find…a box! Opening the box-in-a-box, you see the driver CD nestled in a foam square. Then you pull those off and see the card itself with the accessories in their own little foam cutout. The card is definitely well-protected.
The accessory stack is strong as video cards go. You get a speed setup guide and driver disc in the little box, though any overclocker with half a brain will skip the disc and run straight to the AMD web site to get the latest driver. The other accessories include a Crossfire connector, VGA-to-HDMI adapter and dual 6-pin PCIe -to- 8-pin PCIe power adapter. That other item is definitely not standard fare.
The long black heatsink is just that, a heatsink – for the power section of the card to assist when you take it sub-zero on dry ice or liquid nitrogen cooling! How cool is that? Not only did they design this card for overclocking (more on that later), they’re encouraging freezing it and helping those that do a great deal by supplying this heatsink right out of the box. Kudos ASUS, kudos.
Strong accessories in a box fit for a, well for a high-end graphics card. You thought I was going to say king, didn’t you?
Meet the ASUS HD 7970 DirectCU II TOP
Ladies and gentlemen, here is the main event. The ASUS HD 7970 DirectCU II TOP in the flesh, and boy, is it a good looking card.
Whether or not you’re a big fan of ASUS’ black & red ROG color scheme, you’ve got to hand it to them, they have a great looking three-slot graphics card monster here. Even if you don’t like the black & red scheme, there are only three red lines. The rest is sleek black and silver; svelte, if you will. Anyway, check out the photo shoot.
Ok, ok, wipe the drool off for a bit, let’s snap back to reality (oh, there goes gravity…free virtual cookie if you know where that lyric came from). In that last photo above, you can see the power connectors on the right. Because of the overclocking ability – and by extension amperage draw of this card – they’ve equipped it with two 8-pin PCIe power connectors rather than the reference single 8-pin plus single 6-pin.
You saw it before in the ASUS image, but here are the connectors in the flesh. You can also see why ASUS classifies this card as a 2.5-slot card. The bracket is triple-slot, but you can see the cooler doesn’t quite make it to the bottom of the bracket.
In a card this high-end, you want the back side to look as good as the front and ASUS has obliged by including a backplate.
Zooming in a bit you can see just how much ASUS likes overclockers, and it comes in the form of the ability to connect this card to a motherboard that has the GPU HotWire feature. By soldering wires onto these points (and shorting the two adjacent pads in the photo on the left), you can read and control PLL (the left photo), Vcore and Vmem (the right), running them far over what software control allows.
You don’t have to use extreme cooling for this either. If you want to push farther than software allows and your temperatures are still reasonable (as they easily are with this cooler at the software limit), this allows you to do it.
The drawback is that it requires an ASUS Extreme ROG board to have this feature. I’d like to see them include instructions for using these solder points with variable resistors as well, in case you don’t have an ASUS ROG Extreme board. I’m sure someone can figure that out, but if there was a request to make, that would be it. It’s understandable they don’t necessarily want you to go out of the ASUS ecosystem to get that control, but you’re paying a premium for this card and should have the option.
No, there’s nothing new here, I just thought you’d want one more angle of this great looking card.
Under the Hood
Taking the heatsink off, you can begin to see what separates this card from other cards. Not only is the cooler obviously strong, that power section kind-of jumps out at you, doesn’t it?
There is thermal paste on the GPU-matched copper slug attached to the heatpipes. The memory and MOSFETs have thermal pads for heat transfer. Contact was solid throughout.
Interestingly, rather than splitting the heatpipes evenly, with three on each side, they went with four on one side and two on the other. From the angle in the photo on the right, you can see the MOSFET sink has fins to take advantage of the airflow the fans are putting through the heatsink as well.
ASUS has a nice blown up view of the cooler construction. They claim it’s 20% cooler and 20% quieter than reference (easily believable).
Here is the HD 7970 DirectCU II TOP in the flesh. It’s nice looking as electronics go and deserves its own photo shoot.
Now we get to the power section. ASUS has equipped this card with a 12-phase Super Alloy Power section, which contains upgraded MOSFETs, chokes, 100% Japanese solid capacitors and upgraded SAP CAPs.
As mentioned, there are twelve phases in this line. Two are for the GDDR5 memory and ten are for the GPU. if you look back up at the ‘front’ of the card near the video connectors, you can actually see there are two other phases. This is pending confirmation from ASUS, but I believe those are beefed up phases for the card’s PLL. Thus, there are actually 14 phases on the card all told.
As far as what altered PLL voltage actually does, PLL is mostly used to assist the card in running colder (like, liquid nitrogen kind of cold). While it might help a small amount with overclock stability on ambient, helping the card run better while colder is where that control will have the most benefit.
Here we have the Hynix GDDR5 memory. The card has 3 GB worth and it clocks pretty well actually, even without software voltage control.
Last but not least we have the HD 7970 GPU itself.
So far we have a great looking card with the cooler on and an even better looking one with the cooler removed. Time to put this beast in a machine.
Our test setup is the same as that used previously other than the ‘pushing the limits’ and Eyefinity testing sections, for which the motherboard was swapped out. That swap didn’t lead to a difference in scores really (it was tested) so it’s no big deal.
|MB||ASUS Maximus V GENE / Maximus V Extreme|
|RAM||G.Skill RipjawsX DDR3-2133|
|GPU||ASUS HD 7970 DirectCU II TOP|
|OS||Windows 7 Professoinal x64|
The cards we’re comparing have been tested at the same settings, but on different motherboards per the Overclockers’ Updated Video Card Testing Procedure.
|EVGA GTX 660 Ti Superclocked|
|Sapphire HD 7870 Flex Edition|
|Powercolor PCS+ HD 7850|
|HIS 7950 IceQ Turbo|
|ASUS GTX 670 DirectCU II TOP|
|MSI GTX 680 Lightning|
|AMD HD 6990|
There is stiff competition, especially from the MSI GTX 680 Lightning, which is right in the market segment at which this card is aimed.
ASUS’ GPU Tweak software is another example of ASUS software engineers writing quality overclocking software. Like AISuite, its implementation is seamless, it is easy to use and it gets the job done.
Unfortunately it’s not quite as strong as MSI’s Afterburner for their Lightning cards. While this card obviously has the capability to vary its memory and PLL voltages, you don’t get that control in GPU Tweak and must use the GPU HotWire feature to adjust them.
Additionally, the GPU voltage was formerly capped far lower than the card is capable of running, at only 1182 mV. While maxing out the overclock and cranking the fan to 100%, the card barely tops 55°C. There is much more gas in this card’s tank than software would have allowed you to draw from it.
Fortunately, in the middle of typing this review, ASUS has come out with a fix to that particular problem. GPU Tweak now allows for up to 1400 mV, giving you plenty of voltage control on any reasonable air or water cooling. Since the new software came into play after running the benchmarks and overclocking the card for the graphed results, we’ll reserve higher voltage results for “Pushing the Limits”.
In addition to GPU Tweak and monitor, ASUS has skinned their own version of GPUz, similar to their ROG-skinned CPUz. It’s a good looking alternative to regular GPUz.
The software is good at what it does. While it can be improved, what it does accomplish it does without issue. No complaints about what it has, just a few wishes about what it lacks.
Cooler Performance & Power Consumption
Before getting to performance it’s always good to see how well the cooler works and how much power the card draws.
The cooler performs very admirably. The only card that runs cooler in this comparison is the GTX 670 DirectCU II TOP, which also has a DirectCU II cooler on it. When run for longer in Heaven, even it loses to the stronger fans, extra heatpipes and deeper fins of the HD 7970’s version of the DirectCU II cooler.
I didn’t include them in the graph because I didn’t run them personally, but if you look back at the MSI GTX 680 Lightning’s temperature results, this card runs just a few degrees warmer.
Remember, these are performed with the stock fan profile too. When you make your own custom fan profile, you can make the fan run faster, which will keep it even cooler than this. As mentioned previously, with full voltage applied and pushing all the MHz the card has at that voltage, the GPU barely got to 55 °C.
Importantly, even on full, the fans on the DirectCU II cooler aren’t very loud at all. Fan noise is nonexistent; the only thing you’re hearing is airflow. It’s not even that loud, and certainly quieter than squirrel-cage style coolers.
Power consumption isn’t a huge deal for us but we definitely should run the numbers for our readers.
As you can see, this card isn’t as efficient as the GTX 670 DCU II TOP. Again, looking back at the MSI GTX 680 Lightning review, its power consumption came in less than the HD 7970 DCU II TOP, but only by a few watts. Heaven was the biggest difference at 12 W. 3DMark 11’s difference was merely 4 W.
From both temperature and efficiency standpoints, the difference between the GTX 680 Lightning and this HD 7970 is certainly nothing to call home about. The two are basically equals here and the difference will come in performance.
Overclocking this card was a breeze. Crank the voltage, raise MHz until it crashes, back off & profit. The 24/7 overclock, stable for every benchmark and game I could throw at it except for 3DMark Vantage (which reduced 10 MHz on the GPU for some reason), ended up being 1200 MHz on the GPU and 1750 MHz (7000 MHz quad-pumped GDDR5-style) on the memory.
As mentioned, this GPU has a lot left in the tank with the newly added voltage increase. 1200 MHz was gained with a mere 1182 mV. You’ll see just how much it has in its tank in “Pushing the Limits”!
As usual, we’re going to start off with synthetic performance, then move on to gaming performance.
First up is oldie-but-goodie 3DMark03. As you can see, Kepler doesn’t particularly care for 03 and the 7970 easily takes out the competition here.
Moving on to more modern times, Vantage is a great DirectX 10 test. Since all of our games (and indeed most modern games) take advantage of DX11 features, this is our only DX10 test. As people still play DX10 games, even if they aren’t buying new ones, it’s still a worthy test.
Vantage shows two results, both of which I kind-of expected. The way the Kepler vs. Tahiti Pro battle has shaken out, the former seems to be better when operating at stock and the latter seems to be better when overclocked – primarily because unlike Kepler, Tahiti Pro still gives you voltage to play with. NVIDIA has so restricted Kepler’s overclocking ability, when you overclock them as far as their Power Tune limit will allow, they just can’t reach Tahiti Pro performance levels; and that is borne out here. At stock the GTX 680 Lightning comes out ahead by ~800 3DMarks, but when overclocked, the HD 7970 DirectCU II TOP (hereinafter HD 7970 DCT) leaps over the Lightning’s result by over 1200 3DMarks.
3DMark 11 introduces DX11 features, of which Tessellation is one of the most arduous. Kepler has been especially good at DX11 performance when Tessellation is involved.
The GTX 680 Lightning flexes its muscle here, trouncing the HD 7970 DCT at stock and still beating it by a few hundred overclocked. The HD 7970 DCT does make up a ton of ground when you overclock it though.
Heaven is another DX11 bench, with full featured testing.
Kepler isn’t as strong in Heaven as it was in 3DMark 11. The stock GTX 680 Lightning just edges out the HD 7970 DCT, but the DCT gives it a good beat down when they’re both overclocked.
Moving on to the game tests, as usual we’ll tackle them in alphabetical order, starting with the Aliens vs. Predator DirectX 11 Benchmark.
The HD 7970 DCT starts out strong and only gets stronger, trouncing the competition in this benchmark.
Batman is the same story, with the HD 7970 DCT mopping up, beating the GTX 680 Lightning handily at stock and trouncing it overclocked.
This is starting to look like a familiar story. Stock gets a small’ish win over Kepler’s best, overclocked comes in markedly ahead.
Here we have the first ding in the HD 7970 DCT’s armor, with Kepler doing a better job in Civilization V all around. The difference isn’t huge, but it is a win for Kepler here.
Dirt 3 has some great competition. Similar to the synthetic benchmarks, it shows the HD 7970 DCT losing by a few FPS at stock and winning by a few FPS when overclocked.
Last, but certainly not least, we have the most difficult game benchmark in our testing suite. Metro brings GPUs to their knees, with even the most high-end GPUs unable to muster 60FPS with everything turned up. In Metro 2033, the HD 7970 DCT comes out on top, by a little bit at stock and by a good margin in this kind of bench when overclocked.
AMD Eyefinity Testing
With GPUs like AMD’s HD 7870 and NVIDIA’s 660Ti able to handle games at 1080p without too much trouble on current and past titles, it’s at higher resolutions that GPUs this strong really separate themselves. It’s important to note, the overclocked Eyefninty runs were completed at 1260 MHz on the GPU, 60 MHz over the overclock above. This is because the new version of GPU Tweak came out before completing the Eyefinity testing. These game tests were run in three-monitor Eyefinity at 5760 x 1080.
As you can see, at stock the HD 7970 DCT beats out the GTX 670 most of the time, even when the latter is overclocked. When you overclock the HD 7970 DCT to its max stable 24/7 overclock, it just runs away with everything, most of the time beating out last year’s behemoth HD 6990. Very impressive.
This screenshot was taken after playing Battlefield 3 multiplayer for over an hour (without so much as a single frame lag I might add). The GPU voltage was set at 1319 mV with the GPU running 1260 MHz. Memory was the same overclock as before at 1750 MHz. After an hour, heavily overclocked running Eyefinity in a 26 °C room and with a custom fan profile, the DirectCU II cooler didn’t even make it to 70 °C, topping out at 67 °C with the fan operating at ~80%. How’s that for cooler performance?
Pushing the Envelope
You’ve gotten to know the card through benchmarks and games above, but in the middle of the review process, ASUS came out with a version of GPU Tweak that expanded the available GPU Vcore to a whopping 1400 mV! This does mean you’ll likely get higher 24/7 overclocks than what you saw above. 1200 MHz is a walk in the park at the previously low 1182 mV.
One thing you should know is that you probably don’t want to just throw 1.4 V at an HD 7970 and go to town. There are possible issues when overclocking at higher voltage like that. For instance, on this particular GPU, if you ran the Vcore over 1.319 V, it got angry and started artifacting like crazy. So just because the voltage is there doesn’t mean you necessarily want to use it. Consider yourself warned.
Anyway, now that we have some voltage to play with, let’s beat the snot out of the HD 7970 DirectCU II TOP and see where it gets us!
In case you don’t want to comb through all those screenshots, the scores are in the picture captions and the top core speed per benchmark is in this handy-dandy chart.
|3DMark Vantage||1295 MHz|
|3DMark 11||1325 MHz|
|HWBot Heaven||1315 MHz|
That’s an average 1313 MHz overclock! It’s quite impressive really. At very close to the same voltage (1.3V), the reference HD 7970 from AMD topped out at 1248 MHz. To gain so much over the reference design means ASUS did a lot right with this card. Add in the fact that you can push voltage even farther via GPU HotWire (under dry ice or liquid nitrogen people…don’t go over 1.4V on air!), then you’ve got a winning card, on air and under colder conditions.
Now, those of you that do want to take this card cold may consider having your soldering iron handy. This is not just for the VGA HotWire feature, but also for the capacitor and inductor positioned where a GPU pot may go. This is best described with photos.
In our photo on the left you can see what might be in the way. The photo on the right, courtesy OClab.ru, shows you the parts moved to the back of the card. This should be child’s play for anyone half-way decent with a soldering iron. Just know what to expect if you want to mount a GPU pot to this card. When mentioned to ASUS, they said they’ve tried pots on this card and those components weren’t in the way, so it likely varies by what GPU pot you use. Just know this is a small issue and you might need to perform a slight modification.
Final Thoughts & Conclusion
You have seen the good, the okay and the exceptional. The only “bad” thing about this card is that cap/coil combination that might interfere with a GPU pot, but that will not hinder extreme overclockers (who have a soldering iron anyway) and compared to having to actually volt-mod the card – instead being handed the capability with GPU HotWire – that’s a walk in the park.
Overclocking this card was a blast. Even before ASUS introduced higher voltage control it had stout results. Now that there is even more voltage to work with, you can push even higher than I did for 24/7 clocks. The cooler is definitely up to the task. As you can see when pushing the limits above, it is also a great card for competitive overclockers – cooling is your only limitation. It won’t even get hot enough to hurt itself with the available voltage, but will need colder temperatures to really take things to the next level.
It does bear mentioning that GPU Tweak does not have voltage control of the memory. They mostly get a pass because you can control it via VGA HotWire, but MSI lets you control memory voltage via Afterburner. ASUS should do the same with GPU Tweak. I brought this up to ASUS and their answer was that it required another hardware controller to introduce memory voltage; it’s not like a simple vBIOS or software update. Adding that controller would have delayed getting the card to market and added cost. Considering the memory’s already stellar overclock – to a spectacular 1750 MHz (350 MHz over stock!) – they likely made the right decision. If you absolutely must have voltage control, use VGA HotWire…or wait for the HD 7970 Matrix that should be coming soon.
In benchmarks and games the HD 7970 DirectCU II TOP really struts its stuff. Versus the GTX 680 Lightning at stock was a stiff competition, with benchmarks and games split right down the middle – each card beat the other five out of ten times. Unfortunately for the GTX 680 Lightning, the HD 7970 DirectCU II TOP overclocks like a banshee, beating out the overclocked GTX 680 in everything but Civilization V and 3DMark 11, sometimes by a very solid margin. As we found out, this card is also a great choice for those that want to run an Eyefinity setup.
What’s great is that ASUS isn’t gouging for this card. I half expected it to come in around $550.00 with all of the features included (and with it beating the GTX 680 Lightning so effectively). Nope! The ASUS HD 7970 DirectCU II TOP isn’t available on Newegg right now, but its little brother HD 7970 DirectCU II (non-TOP) is, and for only $434.99. There is even a $20.00 mail-in-rebate right now, making it $414.99. TOP cards are more highly binned for the increased stock clocks, so their availability is a little more limited. When they are available (a new shipment of these should get to eTailers, including Newegg, in ~5-10 days), ASUS prices the card at a mere $20 over the non-TOP, at $459.99 – but also with a $20 MIR, making it $439.99.
Even at $459.99, you’re getting a lot of GPU for your money. There is nothing but good coming from ASUS with this card and the ASUS HD 7970 DirectCU II TOP is unequivocally Overclockers Approved.
Click the stamp to find out what this means