[W1zzard]

Introduction

Launched amongst much fanfare earlier this year, It's now time for AMD's Graphics CoreNext architecture to get down to serious business: driving a mainstream GPU that offers killer value at price-points which most people will end up buying. AMD today launched the Radeon HD 7700 series, based on its spanking new silicon codenamed "Cape Verde".


What makes this launch a particularly monumental challenge for Graphics CoreNext is that it now has to deliver on its biggest design goal, that of being a more efficient number-cruncher than previous-generation VLIW architecture. This efficiency is supposed to show in relative performance per mm² (taking the new 28 nm fab process into account), performance per Watt, and in more layman terms, performance to stream processor count.

But first, a little history lesson. AMD addressed the sub-$200 market with its first DirectX 11 generation of GPUs using the Radeon HD 5700 series, based on the 40 nm "Juniper" silicon. Since the following HD 6000 series was also based on this process, and AMD had achieved higher performance targets with "Barts", it decided to reshuffle the higher-end lineup, give Barts the HD 6800 series, and since Juniper was the only GPU smaller than Barts, re-brand it to the HD 6700 series, to everyone's disgust including ours. With the transition to the new 28 nm fab process and a new number-chomping architecture, Graphics CoreNext, designing a new GPU became inevitable for AMD. Hence, Cape Verde. Products based on this chip, the Radeon HD 7770 and Radeon HD 7750, are touted to be true successors of the HD 6700 series.



We also have the following reviews for you today:

• AMD Radeon HD 7770 (reference design)
• HD 7750 & HD 7770 in CrossFire
• ASUS Radeon HD 7770 DirectCU Review (custom cooler & overclocked)
• HIS Radeon HD 7750 iCooler (custom cooler)
• MSI Radeon HD 7770 OC (custom cooler & overclocked)
• XFX Radeon HD 7770 Black Edition Super OC Review (custom cooler & overclocked)

Architecture

Cape Verde is a downscale from the "Tahiti" silicon, on which higher Radeon HD 7900 series parts are based. There are fewer number of redundant components, so Cape Verde is left functionally-identical to Tahiti, but is smaller, built for more affordable graphics cards. Cape Verde also retains the basic hierarchy of the architecture as implemented in Tahiti. A command processor takes input from the host machine, decodes them, and does the groundwork for the number-crunching area, the Graphics CoreNext clusters, which then perform all the shader and math-intensive processing. The Raster Operations area does the final leg of the processing, and the information is forwarded to the display logic. All components are interconnected to an L2 cache, that works as a very fast scratchpad for the GPU, and of course, the memory controllers.


Cape Verde has 10 Graphics CoreNext Computing Units (GCN CUs), which total up 640 stream processors. The chip has 40 TMUs, and 16 ROPs. It features a 128-bit wide GDDR5 memory interface, with which it communicates with 1 GB of memory. The chip retains the display logic of Tahiti, which lets you connect up to 6 displays in Eyefinity for productivity usage. The GPU also features PCI-Express Gen. 3.0 support, which increases bandwidth between it and the rest of the system. While we doubt the chip really needs 32 GB/s of system bandwidth, PCIe Gen 3.0 could come handy when connected in configurations with lower number of PCIe lanes (such as x8, x4, or even x1), as PCIe Gen 3.0 has more bandwidth per lane.


With the new HD 7000 series, AMD also introduced what it refers to as ZeroCore Technology. Simply put, this feature reduces power consumption of the GPU down to zero, by gating power to it, when the system is idling for extended periods of time, when the displays are blanked. In this power state, the graphics card draws less than 3W of power, making it extremely energy-efficient. The typical board power figures for the Radeon HD 7700 GPUs are also claimed by its makers to be extremely low.

PowerColor HD 7770 1 GB

PowerColor sent us a card that is pretty much identical to the AMD reference design. Only the cooler has undergone very minor changes on the outside. Its internals are the same as on the AMD board, clock speeds are also at reference design level.

Radeon HD 7770 Market Segment Analysis

	Radeon HD 5750	Radeon HD 5770	Radeon HD 7750	GeForce GTX 550 Ti	Radeon HD 6790	Radeon HD 6850	GeForce GTX 460	GeForce GTX 460	Radeon HD 6870	Radeon HD 7770	PowerColor HD 7770	GeForce GTX 560	GeForce GTX 560 Ti
Shader Units	720	800	512	192	800	960	336	336	1120	640	640	336	384
ROPs	16	16	16	24	16	32	24	32	32	16	16	32	32
Graphics Processor	Juniper	Juniper	Cape Verde	GF116	Barts	Barts	GF104	GF104	Barts	Cape Verde	Cape Verde	GF114	GF114
Transistors	1040M	1040M	1500M	1170M	1700M	1700M	1950M	1950M	1700M	1500M	1500M	1950M	1950M
Memory Size	1024 MB	1024 MB	1024 MB	1024 MB	1024 MB	1024 MB	768 MB	1024 MB	1024 MB	1024 MB	1024 MB	1024 MB	1024 MB
Memory Bus Width	128 bit	128 bit	128 bit	192 bit	256 bit	256 bit	192 bit	256 bit	256 bit	128 bit	128 bit	256 bit	256 bit
Core Clock	700 MHz	850 MHz	800 MHz	900 MHz	840 MHz	775 MHz	675 MHz	675 MHz	900 MHz	1000 MHz	1000 MHz	810 MHz	823 MHz
Memory Clock	1150 MHz	1200 MHz	1125 MHz	1026 MHz	1050 MHz	1000 MHz	900 MHz	900 MHz	1050 MHz	1125 MHz	1125 MHz	1002 MHz	1002 MHz
Price	$110	$105	$110	$120	$125	$135	$140	$140	$155	$160	$160	$170	$210

Packaging

Contents

You will receive:

• Graphics card
• Driver CD + Documentation
• Analog VGA Adapter
• Mini-DP to DP Adapter

The Card

PowerColor has chosen to use the same heatsink as on the AMD reference design, with slightly different branding on the outside.


The card requires two slots in your system.


Display connectivity options include one DVI port, one full size HDMI port and two mini-DisplayPorts. You may use all the outputs at the same time, thanks to AMD's superior display output architecture.

An HDMI sound device is included in the GPU, too. It is HDMI 1.4a compatible which includes HD audio and support for Blu-ray 3D movies. The DisplayPort outputs are version 1.2 which enables the use of hubs and Multi-Stream transport.


You may combine up to two HD 7770 cards from any vendor in a multi-GPU CrossFire configuration for higher framerates or better image quality settings.


Pictured above are photos of the front and back, showing the disassembled board. High-res versions are also available (front, back). If you choose to use these images for voltmods etc, please include a link back to this site or let us post your article.

A Closer Look

PowerColor's thermal solution uses a rather simple approach that works without heatpipes or a fancy copper plate.


The card requires a single 6-pin PCI-Express power cables for operation. This power configuration is good for up to 150 W of power draw.


For voltage control the card uses the ST L6788A chip, which is the same as on many HD 5770 models. While it does offer software voltage control it severely lacks in the overclockers department. For example, it is not possible for software to read the current voltage, unless the chip is running on manual voltage mode (which is not the case when the card is at stock, with stock drivers).


The GDDR5 memory chips are made by Hynix, and carry the model number H5GQ2H24MFR-T2C. They are specified to run at 1250 MHz (5000 MHz GDDR5 effective).


AMD's new Cape Verde graphics processor introduces a new shader architecture, it is also the second GPU to be produced on a 28 nm process at TSMC. The transistor count is 1.5 billion.

Test System

Test System - VGA Rev. 16
CPU:	Intel Core i7 920 @ 3.8 GHz (Bloomfield, 8192 KB Cache)
Motherboard:	Gigabyte X58 Extreme Intel X58 & ICH10R
Memory:	3x 2048 MB Mushkin Redline XP3-12800 DDR3 @ 1520 MHz 8-7-7-16
Harddisk:	WD Caviar Blue WD5000AAKS 500 GB
Power Supply:	Antec HCP-1200 1200W
Software:	Windows 7 64-bit Service Pack 1
Drivers:	NVIDIA: 285.62 ATI: Catalyst 11.12 HD 7950 & 7970: 8.921.2 RC11 HD 7750 & HD 7770: 8.932.2
Display:	LG Flatron W3000H 30" 2560x1600

Benchmark scores in other reviews are only comparable when this exact same configuration is used.

• All video card results were obtained on this exact system with the exact same configuration.
• All games were set to their highest quality setting unless indicated otherwise.
• AA and AF are applied via in-game settings, not via the driver's control panel.

Each benchmark was tested at the following settings and resolution:

• 1024 x 768, No Anti-aliasing. This is a standard resolution without demanding display settings.
• 1280 x 1024, 2x Anti-aliasing. Common resolution for most smaller flatscreens today (17" - 19"). A bit of eye candy turned on in the drivers.
• 1680 x 1050, 4x Anti-aliasing. Most common widescreen resolution on larger displays (19" - 22"). Very good looking driver graphics settings.
• 1920 x 1200, 4x Anti-aliasing. Typical widescreen resolution for large displays (22" - 26"). Very good looking driver graphics settings.
• 2560 x 1600, 4x Anti-aliasing. Highest possible resolution for commonly available displays (30"). Very good looking driver graphics settings.

Aliens vs. Predator

Aliens vs. Predator is based on a merger of the Aliens and the Predators franchise: two legendary alien species that are in conflict with each other, fighting to the death with human marines caught in between. The first person shooter game was developed by Rebellion Studios, who also developed the first AVP PC title and released in February 2010. It is one of the first DirectX 11 games with support for new features like tesselation, which is why AMD heavily promoted it at the time of their DX 11 card launches. We use the AVP benchmark utility with tesselation and advanced DX11 shadows enabled.

Batman: Arkham City

Batman is back on the LCD screen with Arkham City, a sequel to Batman: Arkham Asylum, by Rocksteady Games and WB. It was released to the PC platform in November. Batman is imprisoned in Arkham City, an infamous district of the DC Universe that contains the scum of Gotham, most of which Batman helped get in there. In order to get out he must go through scores of baddies, and encounter many of the iconic super-villains along the way. He's not entirely alone.
Batman Arkham City uses the same Unreal Engine by Epic, as Arkham Asylum, but thanks to the engine's modularity, it has been overhauled, outfitted with the latest technologies, including a graphics engine that takes advantage of DirectX 11.

Battlefield 3

Arguably the most anticipated online shooter title among real gamers - PC gamers, Battlefield 3 is the latest addition to some of the most engaging online multi-player shooter franchises. It combines infantry combat with mechanized warfare including transport vehicles, armored personnel carriers, main battle tanks, attack helicopters, combat aircraft, pretty much everything that goes into today's battlefields. The infantry combat is coupled with role-playing elements, which makes the experience all the more engaging. It also has a single-player campaign which added a few gigabytes to its installer.
Behind all this is a spanking new game engine by EA-DICE, Frostbite 2. It makes use of every possible feature DirectX 11 has to offer, including hardware tessellation, and new lighting effects, to deliver some of the most captivating visuals gamers ever had access to. Not playing this game on PC is grave injustice to what's in store. Faster PCs are rewarded with better visuals.

BattleForge

BattleForge, a card based RTS, is developed by the German EA Phenomic Studio. A few months after launch the game was transformed into a Play 4 Free branded game. That move and the fact that it was included as game bundle with a large number of ATI cards made it one of the more well known RTS games of 2009. You as a player assemble your deck before game to select the units that will be available. Elemental force choices can be from forces of Fire, Frost, Nature and Shadow to complement each other.
The BattleForge engine has full support for DX 9, DX 10 and DX 10.1, we use the internal benchmark tool in DirectX 11 mode with highest settings to acquire our results.

Call of Duty 4

Call of Duty 4 is a first-person shooter that is built on the award winning Call of Duty Series. It is the first version to play in modern times. In a near-future conflict between the United States, Europe and Russia you get to play as a United States Marine and a British SAS operative. The engine is Infinity Ward's own creation and has true dynamic lighting, depth of field, dynamic shadows and HDR. Even though the game plot is scripted you will find yourself in intense battles, often working together with computer controlled team mates. Later installments of the Call of Duty Series use the same game engine, so this test is also representative of Call of Duty: Modern Warfare 3 performance.

Civilization 5

Sid Meier's Civilization V (or Civ 5 in common jargon), is the latest addition to the franchise of masterfully-crafted realtime strategy games that let you play God to a nascent civilization of your choice all the way up to the space-age. Civilization V uses large 3D worlds that are procedurally-generated, and takes advantage of hardware tessellation features offered by DirectX 11 to exponentially step up complexity of cities, models, terrains, and objects. It is also expected of this generation of GPUs to handle the larger texture loads that come with the eye-candy.

Crysis

After the tremendous success of Far Cry, the German game studio Crytek released their latest shooter Crysis in 2007. The game was by far the most hyped and anticipated game in 2007, and forums were full of "Can my system run Crysis?" threads because of the high hardware requirements of this game. Just like in Far Cry the plot evolves on a small island with a thick and richly detailed jungle world. A lot of attention has been given to small details like accurate physics. For example when you fire on a tree trunk, it will shatter and the tree will fall over leaving a stump behind. Enemies in a car can be stopped by shooting the tire of the car. The game graphics are top notch, even today, yet the game still runs well on most computers.

Crysis 2

Crysis 2 takes the player into an alien-infested New York City. The game adds a tactical options mode that allows several approaches to attack a heavily infested enemy location. The new Nanosuit 2.0 that the player uses offers more freedom in ability use, for example multiple abilities can be used at the same time. To better accomodate a given play style weapons can be customized with silencers, laser sights or even a sniping scope.
For rendering Crytek's CryEngine 3 is used which comes with reduced system requirements compared to the first Crysis game. Since Crysis 2 is a multi-platform game, with major development focus on console, the graphics on launch day were only DirectX 9. DirectX 11 functionality was added later in a patch. We use the DX11 version and the high-res texture pack for our benchmarking.

DiRT 3

The latest addition to the Collin McRae Rally franchise, DiRT 3, of multi-format rally motorsport. DiRT 3 introduced more of the same great racing experience Collin McRae DiRT 2 gave you, but with better gameplay, and the new Gymkhana freestyle motor-acrobatics mode, which you'll more likely love than hate. It uses a more polished, performance-optimized version of the EGO engine, version 2.0, which takes advantage of more DirectX 11 features than version 1.0 used on Collin McRae DiRT 2, did.

Dragon Age II

Dragon Age II is the second game in BioWare's Dragon Age franchise and was released in March 2011. As player, named Hawke, you will be able to pick your hero from several classes and grow him over the course of the adventure. Gameplay takes you through a linear narrated story of Hawke's rise to become the legendary "Champion of Kirkwall".
BioWare's Lycium Engine has support for DirectX 11, using tesselation, advanced dynamic lighting and camera effects like depth of field. We benchmark the DX11 version with details set to highest.

Hard Reset

Developed by Flying Wild Hog, a studio that prides itself with the fact that its creation is PC-exclusive (bless them), Hard Reset is a first person shooter that's set in a future cyberpunk setting of a dystopian world. It reintroduces many of the gameplay mechanics that made classics such as Quake wicked fun, which today's tactical military shooters eroded, creating a 'void' for.
The game uses the studio's in-house Road Hog Engine, which isn't particularly heavy on new-generation DirectX features, but can still get taxing with some GPUs.

Metro 2033

Metro 2033 is a first-person shooter game that is set in a post apocalyptic Moscow - as the name suggests inside the metro system. You will fight mutants or other humans who like to take away your shelter. The game has many gameplay elements similar to STALKER, also the engine has similar features. This is because two STALKER engine programmers left GSC Game World and started their own company which is now making Metro 2033.
The engine has support for all the latest eye candy like DirectX 11 and Tesselation. Unfortunately it leaves a less than optimized impression, making it a candidate to surpass Crysis for the highest hardware requirements. We test in DirectX 11 mode with details set to "Very High".

STALKER: Call of Pripyat

STALKER: Call of Pripyat takes places shortly after the events of the previous game STALKER: Shadow of Chernobyl. The player is one of many stalkers who are attracted by the Zone in hope of finding fame, wealth and artifacts. Over the course of the game you meet Strelok, the protagonist of the first STALKER game and team up with him to progress through the Zone.
An updated X-Ray Engine 1.6 powers the game with support for DirectX 11 using Compute Shaders for improved shadow rendering and tesselation to improve model quality.

StarCraft II

StarCraft II, released in July 2010, is a sequel to Blizzard's award-winning strategy game StarCraft. In the 26th century three species Terrans, Protoss and Zerg are at war. The campaign takes you through many missions on different planets where you have to face the various enemy factions, sometimes several of them. StarCraft II features a similar number of units as the original game, some of them new. Due to the massive success of the first game, Blizzard chose to focus large aspects of the game on multiplayer combat through Battle.net. The campaign serves as a good introduction to units and concepts and competitive multiplayer is where the action is at.
The StarCraft 2 engine supports only DirectX 9, but several patches have improved rendering quality and available options considerably. We test using a recorded 1 vs. 1 multiplayer replay in the late game phase. Please note that Star Craft II is very CPU limited on high-end cards, especially on lower resolutions, so you may not see much scaling between some cards.

Total War: Shogun 2

Set in 16th century feudal Japan, Total War: Shogun 2 takes the player on a quest for domination to conquer and unite the warlords of Japan. Moving away from the European setting of previous Total War games, the game is now designed around principles of the brilliant Chinese general Sun Tzu and his book "The Art of War". Gameplay is switched between real-time battles during which units on the battlefield are controlled and turn-based strategy which enable diplomacy, economy and production management. Taking control of a castles is comprised of several different stages which adds more complexity to warfare.
We benchmark using the highest settings in DirectX 11 mode, which was added via patch after release.

The Elder Scrolls: Skyrim

This isn't just a game, it's a masterpiece. A very large sandbox game that rejects the quality-quantity inverse-proportionality. By genre a role-playing game, TES: Skyrim combines some of the best elements of older titles in the franchise, with some new sandbox elements to churn out an extremely engaging, and addictive game. It makes use of Bethesda's Creation Engine, which isn't visually-intensive in that it doesn't use taxing graphics features, but the game's presentation itself, with large open worlds, end up taxing your hardware. Faster GPUs result in smoother gameplay with most eyecandy turned on.

3DMark 11

3DMark 11 is the very latest from the house of Futuremark, which has given out some of the most comprehensive benchmark applications for PC enthusiasts and gamers. 3DMark 11, as the name might probably suggest, makes use of Microsoft DirectX 11 API, and puts every feature at its disposal to use, creating astonishingly-realistic visuals. In the process, it evaluates DirectX 11 compliant GPUs, and lets gamers know what to expect from games from the near future that make use of the API, in terms of visual realism. The tessellation and depth of field tests are particularly of interest here.

Unigine Heaven 2.0

Unigine Heaven was one of the first demos that supported DirectX 11. Heaven is a technology demonstration for Unigine engine which supports DirectX 9 through 11 and OpenGL too. Version 2.0 adds more scenes and optionally more complex tesselation features. While there is some controversy surrounding the benchmark whether it is an accurate representation of what to expect from future games in regards to DirectX 11 we still chose it as test to get an insight into potential future gaming.

Power Consumption

Cooling modern video cards is becoming more and more difficult, especially when users are asking for quiet cooling solutions. That's why the engineers are now paying much more attention to power consumption of new video card designs. An optimized fan profile is also one of the few things that board vendors can do to impress with reference designs where they are prohibited to make changes to the thermal solution or components on the card.

For this test we measure power consumption of only the graphics card, via PCI-Express power connector(s) and PCI-Express bus slot. A Keithley Integra 2700 with 6.5 digits is used for all measurements. Again, the values here reflect card only power consumption measured at DC VGA card inputs, not the whole system.

We chose Crysis 2 as a standard test representing typical 3D gaming usage because it offers: - very high power draw - high repeatability - is a current game that is supported on all cards due to its DirectX 9 nature - drivers are actively tested and optimized for it - supports all multi-GPU configurations - test runs a relatively short time and renders a non-static scene with variable complexity.

Our results are based on the following tests:

• Idle: Windows 7 Aero sitting at the desktop (1280x1024 32-bit) all windows closed, drivers installed. Card left to warm up in idle until power draw is stable.
• Multi-Monitor: Two monitors connected to the tested card, which use different display timings. Windows 7 Aero sitting at the desktop (1280x1024 32-bit) all windows closed, drivers installed. Card left to warm up in idle until power draw is stable.
• Average: Crysis 2 at 1920x1200, Extreme profile, representing a typical gaming power draw. Average of all readings (12 per second) while the benchmark was rendering (no title/loading screen).
• Peak: Crysis 2 at 1920x1200, Extreme profile, representing a typical gaming power draw. Highest single reading during the test.
• Maximum: Furmark Stability Test at 1280x1024, 0xAA. This results in a very high non-game power consumption that can typically be reached only with stress testing applications. Card left running stress test until power draw converged to a stable value. On cards with power limiting systems we will disable the power limiting system or configure it to the highest available setting - if possible. We will also use the highest single reading from a Furmark run which is obtained by measuring faster than when the power limit can kick in.
• Blu-ray Playback: Power DVD 9 Ultra is used at a resolution of 1920x1200 to play back the Batman: The Dark Knight disc with GPU acceleration turned on. Playback starts around timecode 1:19 which has the highest data rates on the BD with up to 40 Mb/s. Playback left running until power draw converged to a stable value.

AMD's latest graphics processor shows outstanding power consumption characteristics. In idle, power consumption has gone down to less than half of what the previous HD 5770 GPU required. Multi-monitor power is about the same, due to higher memory clocks required to avoid flicker.

In 3D, the new cards use significantly less power than anything on the market, resulting in leading performance per Watt scores.

A new feature of the HD 7000 Series is AMD ZeroCore Power, which will power off the card as soon as the monitor output is blanked, during screen saver for example. For additional power and noise reduction the fan will stop in this state, too. We measured a power consumption of 1.11 Watts for the whole graphics card during ZeroCore Power. As soon as you move the mouse the PC is back immediately, there is no lag or any delay.
Please note that ZeroCore Power seems to engage only when the screen is completely static. If you have an application running that draws to the screen, the monitor will go black, but the card will not enter the low power state or return from it quickly. To avoid this, minimize all applications and let Windows sit at the desktop.

Fan Noise

In the past years users would accept everything just to get more performance. Nowadays this has changed and people have become more aware of the fan noise and power consumption of their graphic cards.
In order to properly test the fan noise a card emits we are using a Bruel & Kjaer 2236 sound level meter (~$4,000) which has the measurement range and accuracy we are looking for.


The tested graphics card is installed in a system that is completely passively cooled. That is passive PSU, passive CPU cooler, passive cooling on the motherboard and a solid state drive.
This setup allows us to eliminate secondary noise sources and test only the video card. To be more compliant with standards like DIN 45635 (we are not claiming to be fully DIN 45635 certified) the measurement is conducted at 100 cm distance and 160 cm over the floor. The ambient background noise level in the room is well below 20 dbA for all measurements. Please note that the dbA scale is not linear, it is logarithmic. 40 dbA is not twice as loud as 20 dbA. A 3 dbA increase results in double the sound pressure. The human hearing is a bit different and it is generally accepted that a 10 dbA increase doubles the perceived sound level. The 3D load noise levels are tested with a stressful game, not Furmark.

Fan noise of the PowerColor HD 7770 is a bit higher than that of the AMD reference design. We have tested many other HD 7770 cards today, and the PowerColor is clearly one of the noisiest HD 7770 cards. However, 32 dbA and 35 dbA are far from noisy, just not as quiet as I would have expected from a card in this performance class.

Performance Summary

The graphs on this page show a combined performance summary of all tests and resolutions from previous pages. Each graph shows the tested card as 100% and all other cards' performance relative to it. A sixth graph summarizes all tests in all resolutions to calculate the total relative performance of the review sample.

Performance per Watt

Using the relative performance scores from the previous page and the typical gaming power consumption result, the following graphs show efficiency of the cards in our test group.

Performance per Dollar

If you are looking for the best bang for the buck, then you will love this graph. We looked up the current USD price of each card on the popular online shop Newegg and used it and the relative performance numbers to calculate the Performance per Dollar Index.

Overclocking

The overclocks listed in this section were achieved with the default fan and voltage settings as defined in the VGA BIOS. Please note that every single sample overclocks differently, that's why our results here can only serve as a guideline for what you can expect from your card.



Maximum stable clocks of our card are 1135 MHz core (14% overclock) and 1510 MHz Memory (34% overclock).

Overclocking is decent, yet at the lower end of the spectrum we have seen on the cards tested today. I'd say a typical overclock is about 1150 MHz core and 1600 MHz memory, so PowerColor's card sits a bit below that.

Overclocked Performance

Using these clock frequencies we ran a quick test of Call of Duty 4 to evaluate the gains from overclocking.


Actual 3D performance gained from overclocking is 16.6%.

Temperatures

Temperatures are great and have plenty headroom for overclocking. Seeing 29°C during idle makes me wonder why PowerColor didn't reduce the fan speed in idle to make the card quieter, like the other manufacturers.

Clock Profiles

Modern graphics cards have several clock profiles that are selected to balance power draw and performance requirements.
The following table lists the clock settings for important performance scenarios and the GPU voltage that we measured. We measure on the pins of a coil or capacitor near the GPU voltage regulator.

	Core Clock	Memory Clock	GPU Voltage (measured)
Desktop	300 MHz	150 MHz	0.88 V
Multi-Monitor	300 MHz	1125 MHz	1.01 V
Blu-ray Playback	1000 MHz	1125 MHz	1.00 V
3D Load	1000 MHz	1125 MHz	1.02 V

CCC Overdrive Limits
Core	1200MHz
Memory	1250 MHz

Value and Conclusion

	PowerColor's card comes at the AMD reference design price of $159 (according to AMD).
	20% performance increase over last generation Excellent energy efficiency Decent overclocking potential Native full-size HDMI & DisplayPort output Adds support for PCI-Express 3.0 and DirectX 11.1 Low idle temperatures Support for multiple independent audio streams
	Price too high to be competitive CCC Overdrive limits too low Lower OC potential than other cards tested today Card could be quieter Voltage controller not very overclocker-friendly
8.5	AMD's new Radeon HD 7770 delivers a substantial improvement over the previous generation HD 5770. The HD 6770 was just a HD 5770 with a "6770" sticker slapped on it, so the upgrade has been overdue. Averaged over all our testing we see more than 20% higher performance from the reference clocked HD 7770 vs. the HD 5770. This puts the HD 7770 on the same performance level as NVIDIA's GeForce GTX 460, or a bit below the HD 6850. We have seen great overclocking potential from the AMD HD 7900 Series, and the HD 7700 Series is just like it. Overclocking the cards well beyond 1 GHz is quite easy. We reached between 1140 and 1180 MHz on the cards tested today. Memory overclocks well, too, resulting in a total real-life performance improvement of about 15%. AMD's new generation of graphics processors has great power consumption: below 70W during typical gaming is a first for this performance class. Idle power consumption is also down, at 7 Watts now, which is great for users who spend most of their time with productivity and rarely game. Overall performance per Watt is leading our charts, only to be bested by AMD's other card released today, the HD 7750. PowerColor's Radeon HD 7770 is a very close to reference implementation of the AMD Radeon HD 7770. It is pretty much the reference design, at same clocks, using the same cooler, but also comes at no price increase. In our testing we noticed slightly increased noise levels and a bit lower overclocking potential. Compared to the tough competition that we have seen from other HD 7770 cards that bring lots of added value to the table, I am not so convinced that PowerColor's HD 7770 has what it takes to impress the customers. Overall the HD 7770 is a good product with lots of potential, if there weren't the sky high price. AMD's officially suggested retailer pricing is "starting at $159", so we'll probably see retailers cashing in on these cards with inflated prices, like on the HD 7970 and HD 7950. Even at $159 the cards are way too expensive. They are up against the GTX 460 which is 20$ cheaper and delivers similar performance. HD 6850 ($135) and HD 6870 ($155) are faster, and give you much more bang for your buck, up to 30% more! If you are willing to shop used, you can find HD 5770 cards for well below $100, that have all the same major features and better price/performance, too. It seems that in its lower mid-range segment, the HD 7770 is the most expensive, least money-efficient card. However, I'm confident that AMD has lots of headroom on pricing for future price wars with NVIDIA. In my opinion a fair price for the HD 7770 would be below $130.