Classic Computer Magazine Archive COMPUTE! ISSUE 146 / NOVEMBER 1992 / PAGE A18

Previewing the Amiga 4000. (microcomputer)
by Denny Atkin

Commodore is slated to introduce a number of exciting new products at the World of Commodore Amiga show in Pasadena, scheduled for September 11-13, including the first of the second-generation Amigas. Although the show will be ready for the history books by the time you read this, magazine lead times (this is being written in late August) force us to delay full coverage of the show until next month's issue. However, Commodore was gracious enough to provide Amiga Resource with early information about the exciting new products it will be introducing. All specifications are preliminary and are subject to change before the products are released.

The view zooms in on a starfilled sky. Twisting and turning, we pass a colorful nebula, then zoom in at 30 frames per second on a planet, a multihued gas giant. A fanfare plays in the background as the credits pop up onscreen. Welcome to Amiga: The Next Generation.

If you're looking for an Amiga that can do warp speed and do it in style, you'll love the new A4000. Equipped with a 25-MHz Motorola 68040 microprocessor, a new graphics chip set, and a 32-bit expansion bus, Commodore is counting on the A4000 to put the Amiga back on the technological leading edge.

Although similar in size and style to the A3000, the A4000 is a completely new design featuring what Commodore calls the Advanced Graphics Architecture. Gone are the familar Agnus and Denise chips; they've been replaced by Alice and Lisa, known together as the AA (Advanced Amiga) chip set. While the AA chips are upwardly compatible with the original Amiga chip set and ECS, they add a number of new graphics modes that put Amiga graphics a step ahead of Supr VGA. No longer are you stuck with only 4096 colors to choose from--the AA chip set provides a full 24-bit palette (16.8 million colors). All of the original graphics modes are supported, along with new 64-,128-, and 256-color modes. In addition, there's a new enhanced HAM mode that supports over 256,000 colors, depending upon resolution. (Commodore says that with certain monitor and screen mode combinations, you could feasibly display all 16.8 million colors simultaneously.) Since the enhanced HAM mode now sports 64 24-bit base color registers, creating pictures without the fringing common in the original HAM mode is relatively simple.

The AA graphics resolutions are the same as those available in ECS: Lo-Res 320 x 200 or, Hi-Res 640 x 200 or 400, ECS VGA 640 x 480 or 960, Super72 800 x 300 or 600, and SuperHires 1280 x 200 or 400. However, you're no longer limited to 4 or 16 colors in the highest-resolution modes--you can now display 256,000-color HAM in any mode, even 1280 x 400! There's also a feature called mode promotion that eliminates the need for deinterlacer circuitry. For instance, a 640 x 400 screen can be automatically opened in ECS VGA 16-color mode instead of standard interlaced Hi-Res. (Of course, interlaced modes are still available for video work.) The AA chips have full 32-bit access to memory, which allows them to perform many operations more quickly. Displaying a 16-color hires, overscan, interlaced Workbench screen no longer causes the rest of the system to slow down. Note that you'll need a VGA or multiscan monitor, such as Commodore's A1960, to utilize these new graphics modes.

Integral to the Advanced Graphics Architecture is version 3.0 of the Amiga operating system. This enhance release includes full support for the AA graphics chips, as well as a number of really cool operating system functions for handling attached screens, mode promotion, dynamic palettes, hi-res sprites, Intuition double buffering, and hypertext. One 3.0 feature that's not really that useful but is quite visually impressive is the ability to use IFF pictures as backdrops on your Workbench screen. There's also a new file system that automatically caches directory entires, speeding up floppy access considerably.

Unlike previous Amigas, the A4000 has no microprocessor on the motherboard. The 25-MHz 68040 is contained on a card that plugs into a 200-pin CPU slot on the motherboard. (This slot is physically and electrically compatible with the A3000's processor slot; it's likely that the 040 card in the A4000 is identical to the one used in the A3000T/040.) This has interesting implications for future Amiga models. I wouldn't be surprised if future AA-based Amigas models. I wouldn't be surprised if future AA-based Amigas with different processors utilize the same motherboard and basic components as the A4000. (The fact that the case identifies it as the A4000/040 seems to back this theory up.) Just change the processor card, amount of RAM, hard drive capacity, and number of expansion slots, and you've created a new Amiga.

Other specifications include four 32-bit Zorro lll expansion slots, three of which have in-line IBM AT ISA connectors while the other has an in-line video slot. As in the A3000, the slots are mounted horizontally on a card that plugs vertically into the A4000's motherboard. Memory is now added using industry-standard SIMM packages rather than the difficult-to-install ZIP RAMs used on the A3000. The A4000 ships with 2MB of Chip RAM and 4MB of Fast RAM; you can add up to a total of 16MB of Fast RAM on the motherboard.

The A4000 ships with the same 1.76MB high-density floppy drive found in the A3000T; there's room for mounting a second drive internally. Unlike the A3000, the A4000's second drive bay is 5 1/4 in size, so you can mount a CD-ROM or tape drive internally. Of course, the A4000 retains the external expansion ports found on all Amigas, including serial, parallel, RGB video, external floppy, stereo audio, keyboard, mouse, and joystick ports. The pinouts on the keyboard port have changed, but the other ports should be fully compatible with those on earlier Amiga models.

Although the A4000 is clearly an incredible machine, a couple of poor design decisions will force performance-minded users--who, I assume, are Commodore's audience for this powerhouse--to add peripherals almost immediately. While most of the A4000's design screams speed, Commodore chose not to equip the machine with the blazingly fast 32-bit DMA SCSI controller found in the A3000 but to instead use IDE circuitry similar to that used in the A600. That probably saves Commodore a few dollars in manufacturing the machine and will save you $20-$30 when you go to add a new hard drive, but the tiny monetary advantage is eclipsed by the severe restrictions imposed by the IDE interface. The SCSI interface found in the A3000 supports up to seven expansion devices simultaneously and allows the instant addition of devices ranging from CD-ROM drives and tape backups to DAT drives and scanners. IDE, on the other hand, is almost exclusively limited to hard drives and supports only two devices. Even worse, IDE's 16-bit-interface has less than half the data transfer speed of a good SCSI implementation.

On the plus side, Commodore engineers are working overtime to finish the mercuric A3090, a Zorro lll 32-bit SCSI-2 controller, in time for the A4000's release.

Also noticeably missing is any support for improved sound. The good old Paula chip is still around, providing the 8-bit, four-voice stereo sound we've become accustomed to over the past seven years. Commodore has talked in the past about adding advanced digital signal processor (DSP) technology to the Amiga series. The A4000 has an internal audio hookup for mixing in stereo audio from internal add-ons, so a DSP could be added later. But like SCSI, it seems like an option that should have been a standard in Commodore's top-of-the-line machine--especially as 16-bit sound and DSP chips are starting to infiltrate the MS-DOS universe. Even Atari's last-ditch effort at staying in the personal computer market, the Falcon 030, has a Motorola DSP right on the computer's motherboard.

There must be a rule that only odd-numbered Amigas can be really cool-looking. The original A1000 is second only to the MindSet in attractiveness of design, and the A3000's slimline case certainly graces any desk it sits on. The A2000, on the other hand, was beautiful only on the inside. Well, it appears that Commodore must have had some left-over cases from their recently-discontinued European PC line, because the A4000 has little to distinguish it from the average PC clone. Only the sloping front panel and the Amiga logo embossed on the case give it a feeling of identity. Still, though, it's what's inside that counts.

Even with these omissions, and the surprising lack of a PCMCIA slot, the A4000 still stands out as a major technological advancement. We'll have an in-depth look at the A4000, along with a report on the World of Commodore Amiga crowd's reaction to the introduction of the Advanced Graphics Architecture, in next month's Amiga Resource.

The A4000 won't be the only thing to excite showgoers in Pasadena. Commodore is slated to introduce a number of other new products at the show, including the American debut of the Amiga 600, Workbench 2.1, the long-awaited A570 CD-ROM drive, an updated AmigaVision, and a PC-compatible palmtop computer.

The A600, reviewed in detail last month, will be available bare or with an internal 40MB hard drive. The machine sports a 7.14-MHz 68000 processor, the older ECS graphics chips, and 1MB of Chip RAM (expandable to 2MB using the A601 board). Both models will be bundled with a number of software packages, including games and Virtual Reality Studio 2.

Workbench 2.1 is an incremental upgrade to version 2.04. It's a disk-only upgrade, so if you've already installed Kickstart 2.04, you'll only need to get the new 2.1 disks. Among 2.1's new features are international language support, more sophisticated scalable fonts, a PostScript printer driver, and a built-in version of CrossDOS that will allow you to read and write MS-DOS floppies on your Amiga. The immediate plan is to support AmigaDOS 2.x on original (A) chip set Amigas and 3.x on AA chip set machines.

The A570 CD-ROM drive will make your Amiga 500 completely CDTV-compatible. (You'll need to have the Super Agnus chip and to have your machine modified to use 1MB of Chip RAM for full compatibility.) Along with the CD-ROM drive, the A570 also adds room for 2MB of Fast RAM and an internal SCSI controller. Commodore may make a model available with a built-in hard drive, or you can add your own.

We'll go into detail on the AmigaVision update in an upcoming issue. It adds a runtime module, a host of new commands for multimedia and CDTV support, and should be a welcome addition to the Amiga multimedia arsenal.

Finally, there's Commodore's new PC-compatible palmtop. Since Commodore hasn't released a portable Amiga, this is actually a device in which many Amigans will be interested. Just use the palmtop for on-the-road writing, planning, spreadsheet work, and note-taking, then use the included serial link to transfer the data to your Amiga. There's a flood of PC palmtops hitting the market right now, all based on the PC/CHIP microprocessor, and Commodore's 10 x 5.25 x 1 inch unit looks very competitive. With Microsoft Works built in, a backlit CGA LCD screen, two PCMCIA expansion slots, 2MB of RAM, and a cable that allows data transfer with PCs and Amigas, this under-two-pound package might just be the way to take your Amiga's data on the road. Price was unavailable at press-time, but look for it to come in at well under $1000. We'll have full pricing and availability info on all these products in upcoming issues.