ATI’s recent announcement of its
Mobility Radeon chip series has the Mac world buzzing. The new hardware has implications for future laptop computer designs throughout the PC and Mac markets. With Apple’s historic emphasis on mobile ATI hardware in its PowerBook and iBook computers, the curiosity of Mac users is understandably piqued. How does Radeon compare to the RAGE 128 Mobility chip used in PowerBook G4s?
To get a better understanding of the new Mobility Radeon chip series and how it works, MacCentral sought information from Darren McPhee — ATI’s product marketing manager for Mobility Radeon.
McPhee reassured us that the new Mobility Radeon chip series are all Mac compatible.
“Yes, absolutely,” said McPhee. “ATI has supported the Mac platform with mobile graphics solutions for a long time.”
McPhee explained that there are four separate chips that comprise the Mobility Radeon series. Two of them are integrated products — they include memory already built into them, while the other two are discrete parts — they don’t have any memory built-in, but support up to 64MB of dedicated video RAM. Each product is designed to address different market segments — some where cost and power consumption are top issues, and some where performance and flexibility are paramount.
“The idea behind the Mobility Radeon was to take specific features from the [desktop] Radeon — the most logical parts for mobile users. Hyper-Z compression, Pixel Tapestry Architecture, what we call Video Immersion, all make up the Mobility Radeon,” said McPhee.
No Hardware Transform & Lighting
McPhee explains that while Mobility Radeon has many similarities to its desktop cousin, the laptop chip lacks integrated hardware transform, clipping and lighting (or hardware TCL) features. Hardware TCL has been cited by developers of 3D applications — including many game makers — as vital to providing cutting-edge performance, since it enables the graphics subsystem of a computer to handle many of the more intense geometric calculations that would otherwise need to be done by the computer’s central processing unit.
McPhee explained ATI’s decision to omit hardware TCL from the Mobility Radeon products.
“When you’re designing silicon geometry for a laptop system, space and power consumption are always important considerations. If we were to add hardware transform and lighting capabilities to Mobility Radeon, it would take more silicon, and consume more power and space.
“We looked at the tradeoff of having Mobility Radeon with or without hardware transform and lighting abilities, and we realized that those functions can be handled just as easily by the central processing unit.”
McPhee recognized that some users — especially gamers — may be disappointed with the decision, but he says that hardware transform and lighting is a technology still early in its usage.
“Hardware T&L is not used to its full potential right now, and it’ll still be a while before it is,” McPhee said. “Also, this is the first of several Mobility Radeon products. It’s entirely possible we could include hardware transform, clipping and lighting functions in a future design.”
Changing with the times
“Radeon is a modular technology,” continued McPhee. “We can look at the mobile parts, examine the marketplace, what our OEM partners want, and what the customers want, and make changes to the technology as the markets change.”
McPhee said that this modular philosophy is key to ATI’s strategy for the Mobility Radeon product line.
“The laptop market is getting a lot more segmented,” McPhee said. “Gamers and video pros want high end systems, there’s a big mainstream market that has to balance price and performance, and there’s also a market for subnotebooks, where low power consumption and a low profile chip design is important.”
McPhee said that he expects this specialization in laptop designs to continue as the industry moves forward.
“There will be segmentation to this market and designs for laptops and portable devices you haven’t seen before.”
Better performance, energy conservation
McPhee explains that even with the absence of hardware transform, clipping and lighting abilities, the Mobility Radeon offers a huge performance improvement over previous generations of ATI mobile chip designs, like the RAGE Mobility 128 chip offered in Apple’s PowerBook G4.
“Mobility Radeon is two and a half, three times faster in some areas,” said McPhee. “It has a lot of new features, too. The Mobility Radeon is capable of modulating clock speed and voltage. The chip supports clock speeds of anywhere from 66MHz to 200MHz.”
McPhee said this will enable laptop computer makers to tailor the performance of the Mobility Radeon chip depending on whether it’s hooked up to a power adapter or running off batteries, much the same way that the CPU of a PowerBook G3 can adopt various energy saving profiles now. McPhee said that this feature is unique in the mobile graphics market.
Sizing up the competition
When asked about Nvidia’s recent entry into the mobile graphics market with its GeForce2 Go chip, McPhee took a broader view.
“I think any chip maker who’s in the mobile market right now is a potential competitor, not just Nvidia and ATI,” said McPhee. “I look at Nvidia’s product, and they’re trying to focus on one segment specifically — 3D performance.”
McPhee said the secret to success in the mobile graphics market is to answer different needs.
“The way you thrive is to offer a family of products that address a lot of different segments. We can do that by hitting the high end, mainstream, and value markets. If you look at our competitors, they are only concentrating on one thing. Some concentrate on power, some on low cost.”
With a 57 percent share in the mobile graphics market according to a recent report, ATI is clearly a formidable competitor for any graphics company looking to gain a foothold in the mobile market.
The big question
In their announcement yesterday, ATI indicated that the Mobility Radeon is currently being evaluated by laptop makers for inclusion in future product designs. We’d be remiss if we didn’t ask McPhee if Apple was on the list.
“I can’t comment on Apple,” said McPhee. “Obviously, though, we’ve had a great relationship with Apple on the mobile side. And if you look at our market share, you’ll recognize that we work with the leading computer manufacturers in the world.”
So, for now, PowerBook users will need to be content with the RAGE Mobility 128 series, which is the featured graphics system in the new PowerBook G4, and was also the graphics chip used by the titanium PowerBook’s predecessor, the “Pismo” PowerBook G3 series. Although slower than the Mobility Radeon, the chip is still faster than most of the competition, so new PowerBook G4 owners haven’t anything to regret.