When AMD announced its attention to focus on mainstream graphics processors, we thought the manufacturer was nuts. Why surrender the top end of the market to arch-rival Nvidia? It took a year, but AMD proved us wrong: The Radeon HD 4770 delivers the best price/performance ratio we’ve seen in a very long time.
How did AMD pack so much performance in a chip that can be mounted on a video card with 512MB of GDDR5 memory that sells for just over a hundred bucks? The company’s engineers took advantage of a new 40nm manufacturing process at the chip foundry TSMC to create an entirely new graphics processor: The RV740. This process enabled them to pack the RV740’s transistors extremely close together, resulting in a chip that’s nearly as powerful as AMD’s costlier Radeon HD 4850, despite being almost half its size.
Features and Design
Squeezing more transistors into less real estate is one obvious benefit, but smaller chips offer other advantages, too. They’re cheaper to build, for one, because more of them can be squeezed onto a single silicon wafer. And since they consume less power, they generate less heat. This, in turn, usually means that they can operate at higher clock speeds. And having less heat to dissipate, smaller chips are easier to cool.
The graphics processor in the PowerColor Radeon HD 4670 we looked at last month, for example, is manufactured using a less-sophisticated 55nm process. It squeezes 514 million transistors into a die that measures 145mm2. The Radeon HD 4770 jams 826 million transistors into a 137mm2 die. More transistors results in more stream processors to handle heavier graphics workloads: The 4770 has 640 of these—twice as many as the 4670. Anyone considering upgrading their PC with this card, however, should be aware that it will require more electrical power than can be provided through the PCI Express bus. Your power supply will need to be equipped with either an extra six-pin cable (labeled PCI-E) or two four-pin Molex cables and an adapter (which HIS does not provide). This additional power requirement isn’t at all unusual—higher-end video cards actually require two six-pin cables—but in the event your power supply doesn’t have these cables, it’s probably not powerful enough to handle this card.
Hightech Information Systems (HIS), which manufactured the board we’re examining today, didn’t stray far from AMD’s reference design; as it turns out, the firm didn’t need to. Its engineers run the GPU at stock 750MHz and the 512MB of GDDR5 memory at 800Mhz. GDDR5 memory transfers data four times each clock cycle, versus twice per clock cycle as in the GDDR3 memory used in video cards based on the Radeon HD 4670. The new chip, however, accesses that memory through a relatively narrow 128-bit memory interface (via two 64-bit memory controllers). In this respect, it’s identical to the older 4670.
HIS put two dual-link DVI outputs on the mounting bracket, which enables the card to support a 32-inch display at its native resolution of 2560×1600. But if you’re fortunate enough to have a monitor that size, you’ll want something more powerful than this card to drive it—especially for gaming. You’ll find an analog TV-out connector nestled between the two digital outputs, but this is limited to composite and S-video; here again, HIS doesn’t provide the cable needed to use it. The company does provide an HDMI dongle if you’d like to install this card in your home-theater PC and connect it to your HDTV or video projector; unfortunately, that will add a good two inches to the depth of your rig and could make it difficult to fit your system back into your entertainment center.
We’ve grown accustomed to lowering our expectations when reviewing videocards in the $100 range, at least as far as gaming is concerned. When we reviewed PowerColor’s card, for example, we reduced the resolution of our benchmark games—Infinity Ward’s Call of Duty 4: Modern Warfare, Ubisoft’s Far Cry 2 and Crytek’s Crysis—to 1680×1050 pixels. We chose that setting because it matches the native resolution of the 22-inch ViewSonic VX2240w LCD monitor we were using. We don’t see a point in playing games at less than 60 frames per second, and a 22-inch display is about as big as you can go with that card and maintain that level of performance.
We felt like a cat in a creamery playing Far Cry 2 and CoD 4 at 1680×1050 here though, with the Radeon HD 4770 delivering the first game at a very smooth 71.6 frames per second (with 4x anti-aliasing enabled) and the second at 60.2 frames per second (in DirectX 10 mode with overall quality settings at high and AA turned off). This emboldened us to push the envelope a bit and crank the resolution up to 1920×1200 to see how the card would perform with our Philips Brilliance 230W display. To our delight, we were able to play CoD 4 at 61.4 frames per second and Far Cry 2 at 57.8 frames per second—just a hair below our minimum requirement of 60 fps.
The card had a more difficult time with Crysis, but it performed much, much better with this benchmark killer than the 4670 did. With resolution set to 1680×1050, overall quality set to medium, and anti-aliasing disabled, the 4770 pumped out 44.6 frames per second—that’s almost twice as fast as the cheaper card. Performance with this game dropped to 37 frames per second at 1920×1200. Although that’s far below our minimum expectations, it’s a remarkable feat for a card this inexpensive.
Fast, cool, and cheap are characteristics we like to see in a video card, and the Radeon HD 4770 clearly boasts all three. You’ll want something more powerful if you intend to crank up the visual effects while gaming on a large display, but if your budget is tight and you can tolerate a few visual jaggies, this card is hard to beat.
- Dual-link DVI
- CrossFireX compatible
- Cooler doesn’t exhaust hot air out of the case
- Requires dongle for HDMI
- 128-bit memory interface