A look at the DTX reference prototype
Now that we've talked about the DTX basics, let's have a closer look at the prototype DTX reference design system from AMD. This system is still very much a work in progress, but it offers a clear sense of AMD's vision for DTX. This is, however, very much a reference design. The chassis and motherboard are not early versions of production hardware; although functional, they exist mainly as guides for AMD's partners.
The hardware inside the box will already be familiar to most TR readers. The motherboard is based on AMD's 690G chipset with Radeon X1200 integrated graphics. We reviewed the 690G earlier this year. Paired up with the 690G is an Athlon X2 BE-2350 CPU, a low-power version of the Athlon 64 X2 that runs at 2.1GHz and has a 45W thermal/power rating. We reviewed the X2 BE-2350 back in June, and then followed up with a power consumption comparison between the BE-2350/690G combo and Intel's Core 2 Duo E4300/G965 chipset combo. If you don't recall the exact details of those articles, don't worry. The long and short of it is that AMD has a very nice offering in this space, with low power consumption, adequate performance, and better graphicsin terms of both performance and compatibilitythan Intel.
Thanks to its smaller complement of components and what must be a fairly efficient power supply unit, we found the DTX reference box to be even more power-efficient than the previous AMD 690G/BE-2350 pairing we tested. At idle, this box pulls only 44W at the wall socket. When running a 3D graphics demo and two instances of Prime95, it tops out at about 88W. Not too shabby, to say the least.
Here's a look at the back of the chassis. This box will convert from a pedestal-secured micro-tower to an extra-small desktop within seconds. One need only to pull out the spring-loaded pedestal and give it a twist, so that it tucks away into the side of the unit. Once laid flat on a desk, the DTX box measures roughly 14" wide, 13" deep, and 3.5" high, using my Yankee-style units of measurement. This is a Full DTX affair, by the way. Mini DTX would be even smaller.
The DTX reference system offers up a standard assemblage of ports, with the notable exception of PS/2 mouse and keyboard connectorsthose have been supplanted by USB. Notice that the two expansion card slots will accommodate only low-profile cards.
This system's prototype status is sometimes readily apparent, like when you attempt to open the cover over the front panel and it tumbles onto the floor, rather than swinging back on a hinge or something. Once the cover is safely lost under your desk, you'll find a small collection of I/O facilities living behind it, including a slim-line DVD drive, a multi-format flash reader, and audio and USB jacks. In the picture, just to the right of the smart card port is what appears to be a cutout ExpressCard slot. However, there's nothing behind the cutout in this prototype.
Popping the lid reveals a neat but tightly placed collection of components. This is a very compact design with little room for expansion. Shuttle's XPCs typically have space for at least one more 3.5" hard drive, but this box does not.
Notice the ducting around the CPU cooler. The area it encloses corresponds to a set of venting holes in the lid of the enclosure, allowing direct airflow to the CPU fan. Our prototype system is pretty darned quiet after it first boots, quiet enough to sit on your desk without the noise becoming a bother, in my view. And I'm picky. But it's louder than it should be after it warms up, in part because there's not another set of venting holes in the lid above the power supply fan. The PSU fan has to work pretty hard to get its job done given the quarter-inch or so of open space between it and the case lid. AMD says it has already tweaked its recommendations to include venting above the PSU fan, so future versions of this design ought to remain quieter during operation.
This angled shot better shows the location of the board's two DIMM slots, among other things.
The chassis holds the slimline optical and hard disk drives in a metal tray that's secured by a single thumbscrew and a sliding lock mech. Just unscrew, side the tray sideways a bit, and it pops out.
Beneath the drive tray is AMD's do-everything front-panel board, code-named Carat 1. This board accepts three internal USB connections and an internal audio header link. From those, it drives the card reader, two USB ports, and two audio jacks.
Here's a look at AMD's "Diamond 2" DTX reference motherboard liberated from the case. Holding it in my hands, I was struck by how close the dimensions are to a Shuttle XPC mobo, although the DTX board is slightly wider.
For a quick visual comparison, have a look at the DTX board next to a common microATX board, the 690G-based Asus M2A-VM HDMI. With room for four expansion slots, the mATX mobo is considerably larger.