Apple will begin shipping its new iMac G5 desktop computer worldwide in mid-September, the company's top marketing executive said this week.

Philip Schiller, Apple's senior vice president of worldwide product marketing, showed off the new machine during a keynote speech at the start of the Apple Expo trade show in Paris. The screen of the new iMac is suspended above the desk like that of its predecessor, but its processor, hard disk and DVD drive are concealed behind the screen rather than in the base.

"A lot of people are going to be asking, 'Where did the rest of the computer go?'" Schiller said.

Three models will be available. The top-of-the-range model has a 20-inch LCD screen with a resolution of 1,680 pixels by 1,050 pixels. It contains a 160G-byte hard disk drive, an optical drive for burning DVDs and a 1.8GHz G5 processor, and will sell for US$1,899. In Europe it will cost €2,059, including value-added tax, Schiller said.

The new machines have two FireWire 400 ports, three USB (Universal Serial Bus) ports, audio line-in, optical audio-out, video out, modem and Ethernet connections at the back of the screen. The speaker grills are concealed in the base of the screen and bounce sound off the desktop up to the user.

The other two models have 17-inch screens, 80G byte hard-disk drives and optical drives that can burn CDs and read DVDs. The 1.6GHz model will sell for $1,299 (€1,399 in Europe) and the 1.8 GHz model for $1,499 (€1,629 in Europe).

Customers choosing the optional Wi-Fi wireless networking and Bluetooth wireless peripherals need only plug in a power cord into the back of the machine and begin surfing the 'Net, Schiller said.

The power button is also hidden around the back, the only raised feature on the rear surface and exactly opposite the "sleep" light on the front "so you know where to find it," Schiller said. "We like to joke that the back of our computer is more beautiful than the front of anyone else's computer."

The machines contain a Geforce FX5200 Ultra 64MB video card connected to an AGP 8x graphics bus, and can hold up to 2G bytes of 400MHz DDR RAM, connected via a 600MHz front-side bus. The hard drives use Serial ATA (Advanced Technology Attachment). The slot-loading optical drive is mounted vertically, top-right of the machine, with the processor bottom left, cooled by three computer-controlled fans. "We measured the iMac running," Schiller said, "and it's quieter than a whisper."

"It really is a breakthrough in personal computing," Schiller told the Apple Expo crowd. "I think that's what Apple is all about."

The design and marketing campaign for the iMac G5 will leave no doubt in consumers' minds what else this computer company has delivered lately. Its smooth, feature-free white face is reminiscent of the minimalist MP3 player, and advertisements are to begin with the phrase, "From the company that brought you the iPod."

"I think the new design will surprise many people," said Technology Business Research analyst Tim Deal. "While I think this was the natural next step for Apple in terms of the evolution of the iMac's all-in-one design, I also think that it is unconventional. It's simple, functional and almost spartan in appearance. The new iMac's design is reminiscent of the iPod screen and I am certain that this was intentional. With the iPod taking a prominent role in Apple's product strategy, it makes sense to capitalise on the iPod's familiar form."