AMD Radeon HD 7770 & HD 7750 Review

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Metro 2033 (DX11)

Metro 2033 (DX11)

For this test we use a walkthrough and combat scene from The Bridge level which starts at the beginning of the level and lasts for about 3 minutes of walking, running and combat. Famerates are measured with FRAPS and Advanced PhysX is turned off.

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Shogun 2: Total War (DX11)

Shogun 2: Total War (DX11)

Due to its very nature, Shogun 2 is a tough game to benchamark since the in-game tool doesn’t accurately convey an in-game experience. So we took a pre-recorded battle which pits three large armies against one another and includes camera zooms, fog, gun smoke and other items. Using a pre-recorded sequence also effectively removes the CPU from the equation since it doesn’t have to process AI.

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The Witcher 2 (DX9)

The Witcher 2 (DX9)

The Witcher 2 may be a DX9 based game but its graphics quality is beyond reproach. In this benchmark we take an area out of The Kayran mission and include one of the toughest effects the graphics engine has in store for the GPU: rain. Throughout this sequence, rain plays a large part but explosions, combat and even some sun shafts are included as well.

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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 this test we use the 3DMark Batch Size test at its highest triangle count with 4xAA and 16xAF enabled and looped it for one hour to determine the peak load temperature as measured by GPU-Z.

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

Let’s start with the reference cards before moving on to the more exotic designs in our lineup. The HD 7770 boasts a relatively large heatsink assembly for its small core and this pairing tends to pay dividends in its temperature results. The HD 7750 on the other hand also posts respectable (though hardly low) numbers considering its Munchkin-sized cooler.

The real standouts of this bunch are the XFX and MSI cards, each one for a different reason. The XFX Double Dissipation heatsink once again posts worse numbers than the reference design but as we will see below, its slightly higher temperatures go hand in hand with some additional benefits. MSI as usual has this section in the bag but its pace in the chart also goes to show how efficient the reference design is.

Finally we have the HIS iCooler HD 7750 which may sport one of the cheapest heatsinks we’ve seen in a long time but it actually seems to work quite well. We would have preferred if HIS had stuck with a single slot solution but we’ll take low temperatures as a consolation prize.

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 Heave 2.5 is used in order to generate a constant load on the GPU(s) over the course of 20 minutes.

Let’s be perfectly honest here: the reference HD 7750 is stupidly loud for such a small, efficient card. Due to its low profile heatsink the tiny fan needs to spin at quite high levels in order to keep temperatures under control and even when at idle, it can easily be heard. Meanwhile, AMD’s HD 7770 heatsink was both quiet and well mannered throughout testing which is a quality we look for in mid level cards.

Among the custom cooled pack, both the XFX and HIS cards stood out with excellent results. The XFX Black Edition in particular shows that some board partners are willing to trade a few degrees for lower decibel readings. MSI also posts some great results but they weren’t all that much better than the reference version.

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 once again use the Batch Render test in 3DMark06 and let it run for 30 minutes to determine the peak power consumption while letting the card sit at a stable Windows desktop for 30 minutes to determine the peak idle power consumption. We have also included several other tests as well.

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.

The 28nm process keeps on setting new benchmarks in the field of power consumption and the HD 7700 series carries on this tradition. The HD 7770 really does hit an excellent performance per watt level and even the highly overclocked XFX version is able to put efficiency first.

 

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Overclocking Results

Overclocking Results

At the risk of sounding like a broken record, the 28nm manufacturing process has allowed AMD’s latest generation to accomplish some impressive overclocking feats. The HD 7770 and to a slightly lesser extent the HD 7750 stick to this tradition in both their reference and non reference forms. There wasn’t a single card that stood out from the pack but the XFX Black Edition with its slightly higher default voltage did edge out the rest of the competition by a narrow margin. With that being said, if you do manage to get your HD 7770 to the 1.12 GHz mark, it should have no issue sticking with –and in many cases beating- a stock HD 6850. The non-reference cooled HD 7750 on the other hand hits 880MHz without breaking a sweat and at those speeds, easily surpasses the GTX 550 Ti. Unfortunately, the reference version was an overclocking dud due to its lackluster heatsink design.

Unfortunately, due to the short turnaround of this review we weren’t able to explore voltage tweaking through MSI’s Afterburner but we’re sure that with a few tweaks and a bit more time, clock speeds could surely be pushed further.


Final Clock Speeds

PowerColor HD 7770 (Ref)

Core: 1105MHz
Memory: 5144MHz (QDR)


XFX HD 7770 Black Edition DD

Core: 1204MHz
Memory: 5304MHz (QDR)


MSI HD 7770 OC

Core: 1122MHz
Memory: 5088MHz (QDR)


AMD HD 7750 (Ref.)

Core: 833MHz
Memory: 4884MHz (QDR)


HIS HD 7750 iCooler

Core: 891MHz
Memory: 4980MHz (QDR)

 

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Conclusion

Conclusion

The HD 7770 has a lot going for it. The 28nm GCN architecture has allowed for high clock speeds, plenty of overclock headroom, a good jump in core per core performance over VLIW designs and excellent all-round efficiency. At first glance, it looks like there is a fair amount of forward progress being made with this spiritual successor to the HD 5770 but on some levels that just isn’t the case. Our hopes a great performing, affordable mid range part came crashing back to earth with the realization that AMD’s $159 SRP is simply out of touch with current market realities.

In its current price bracket the HD 7770 is going up against the $155 HD 6850s of this world rather than lower end NVIDIA offerings and its overall performance just can't measure up to the Barts Pro, particularly in bandwidth heavy situations. In many ways AMD has been a victim of their own success since the HD 6850’s lowered price was a recipe for sales success but it makes the Radeon family’s newest member look positively overpriced by comparison. To make matters worse, for the cost of a few cafeteria lunches you can step up to a $180 GTX 560, a card that simply walks all over Cape Verde.

Comparing the HD 7770 to GPUs that were initially released at a much higher price is hardly “fair”. Rather, to objectively judge forward progress from one architectural generation to the next, let’s take a step back in time and look at the HD 6790. Initially released at $149 nearly a year ago (and now retailing for about $119) this Barts LE-based card manages to play on a nearly level footing with the HD 7770 most games. If you can’t see the ramifications of this, let’s make it clear: $159 doesn’t buy you an ounce more performance now than it did 10 months and a generation of GPUs ago. We can talk all day about how the Cape Verde cores are able to offer similar performance with less power, less heat and less noise but budget conscious gamers don’t usually give a damn about any of that. They care about a great bang for buck ratio and that’s precisely where the HD 7770 falls on its face.

There are however some rays of hope courtesy of AMD's board partners but even these are tempered by the HD 7770’s high starting cost. The XFX Black Edition DD is a great little card that can keep pace with and usually beat an HD 6850. Unfortunately a $180 price tag means it competes against NVIDIA’s vastly more powerful GTX 560 and that’s an unfair fight if there ever was one. MSI’s own HD 7770 OC doesn’t fare all that much better even though its custom heatsink allows for lower than reference temperatures and a diminutive acoustical footprint.

We haven’t talked much about the HD 7750 and it actually deserves a section all on its own since it does tend to stand out for all the right reasons. Aimed directly at the GTX 550 Ti’s market niche, it fails to actually surpass the NVIDIA card on a regular basis but from a price / performance standpoint, there are some flashes of excellence here. A compact $109 card equipped with top notch decoding capabilities is certainly appealing but unlike the HD 7770, which is quiet as a mouse, the HD 7750’s reference design makes an absolute racket. HIS’ iCooler version quiets things down a bit and coupled with its full sized output connectors, we can see this being the go-to card for entry level gamers and HTPC users alike. Sure, we were hoping to see the low end market’s goal posts moved a bit more but the HD 7750 doesn’t hide what it is: a low priced card that’s geared towards large system builders rather than enthusiasts.

While this conclusion may not sound all that positive, there’s actually a whole lot to like about AMD’s newest entries into the sub-$200 market. They perform well, should be widely available at launch and will put some pressure on NVIDIA once pricing (hopefully) levels out. In addition, low power consumption and minimal heat production are great indicators of a card that will live happily in just about anyone’s system, be it a regular ATX setup or a small form factor HTPC.

Unfortunately for AMD, money talks these days and gamers who care about framerates will understandably overlook the HD 7770 since there are comparably priced cards which outperform it by significant margins. Price cuts could turn our opinion on its head but for the time being it looks like AMD is staying the course with a firm $159 introductory cost. The HD 7750 on the other hand may not impress critics with jaw dropping performance but as an inexpensive graphics card, it actually succeeds quite well.