The case might look familiar from the outside, but the Dell Dimension 8400 represents the opening shot in Intel's wholesale overhaul of the desktop PC's core technology. Featuring Intel's new 925X Express (a.k.a. Alderwood chipset), a 3.6GHz Intel Pentium 4 560 processor, and the first PCI Express graphics card we've seen -- the 256MB ATI Radeon X800 XT -- the Dimension 8400 is essentially a showcase for the future of the PC. Gamers and multimedia enthusiasts will be especially thrilled by the hardware and the fast performance.
Despite the new technologies inside it, very little about the Dell Dimension 8400's case has changed in the years since it was introduced as the Dimension 8100. The same rather dull, grey-and-black-plastic exterior opens up like an Oxford English Dictionary, the motherboard and the power supply are attached to one side, the drives on the other. The latching mechanism still irritates us; it requires you to press buttons on both the top and the underside of the case. When you finally pry it open, the case takes up more desk space compared to a standard tower case with a removable side panel.
It's not until you open the Dimension 8400 that you'll be able to see the new features of Intel's 925X Express chipset. Once your eye leaves the processor's huge heat sink, you'll discover one of the prime benefits of the chipset: improved bus architecture. Replacing the decade-old AGP interface for graphics cards, PCI Express (PCIe) features faster data throughput than either standard PCI or AGP slots.
The Dimension 8400 comes with one full-length 16X PCIe slot for the graphics card and one smaller 1X PCIe slot for upgrades such as Gigabit Ethernet cards and others, though cards for the 1x port have not yet been released. Eventually PCIe will replace both AGP and PCI altogether, but until more PCIe cards become available, you'll be glad the Dimension 8400 has three old-fashioned PCI slots, one of which was vacant on our review unit. A pair of 512MB DDR2 SDRAM sticks occupies two of the four system-memory slots, which you can upgrade to 4GB of memory, if for some reason you should find this necessary.
Despite the extreme cooling tactics, the interior of the Dimension 8400 is much neater than the Dimension 8300 cases we've seen. The 925X chipset minimises cable clutter by moving to the smaller Serial ATA cables for connecting hard drives, leaving only one IDE channel and its cumbersome ribbon cable for your optical drives. The Dimension 8400 includes two Serial ATA drives but has ports and 3.5-inch drive bays for up to four SATA drives -- and a maximum of 1.6 terabytes (TB) of storage space. That's right, we said terabytes. You'll find no floppy drive installed in the Dimension 8400, but sadly, Dell also offers no media-card reader to aid interfacing with digital cameras and other devices.
The usual list of legacy ports, plus Gigabit Ethernet, FireWire and six USB 2.0 ports reside on the back panel. A flip-up panel on the front of the system hides an additional pair of USB 2.0 ports and a headphone jack, but they slant downward, making access more difficult than need be if you have the system sitting on the floor. You'll also find a pair of additional USB 2.0 ports on the side of the bundled LCD monitor.