The Dimension 4550 offers the same processing power as the more expensive 8000 line (up to a 3.06GHz Pentium 4), but its maximum RAM caps out at 1GB--still a hefty amount for even digital video enthusiasts. The default hard disk size is only 30GB, but you can expand that to 200GB. A 200GB drive offers plenty of room to install lots of games and store loads of music and video files.

Like its Dimension siblings, the 4000 series features an aesthetically pleasing black-with-gray-accents chassis. Even the mouse, keyboard, and monitor offer the same color scheme as the midsize tower. You can add other peripherals to the 4000, such as a printer or a scanner, and they come in the same matching colors.

A 17-inch CRT, the passable Dell M782, is the de facto display for the Dimension line, but myriad upgrade options are available. If you fancy a flat-panel monitor, for example, Dell offers excellent LCDs ranging from a small but affordable 15-inch 1504FP ($200 extra) to the monstrous--in terms of both size and price--20.1-inch 2000FP ($830 extra). All of Dell's flat panels deliver crisp and colorful images, with sharp, easily readable text.

The 4550 comes with 128MB of DDR SDRAM, but users who plan on gaming or any kind of digital editing should consider upgrading to at least 512MB--this affordable upgrade will run you only another $99 and will make sure you're not limiting the Dimension's performance levels. With a 2.67GHz Pentium 4 processor and that half a gig of RAM, the Dimension 4000s can hold their own against any comparable systems.

While the 64MB NVIDIA GeForce4 MX graphics card offers respectable gaming performance, hard-core users might want to consider upgrading to the ATI Radeon 9700 with 128MB of DDR memory. It'll cost an extra $120 over the NVIDIA card, but the added frame rates and high resolution effects with the latest games make it worth the cost for some users.

The base model comes with a 48X CD-ROM drive. You can opt to add a 16X DVD-ROM drive and a 40X/10X/40X CD-RW drive in the two 5.25-inch drive bays on the 4550, letting you watch DVD movies, burn audio CDs, and create rewriteable backup discs. If you're inclined to move your home movie collection over to DVD, you can opt for the 4X DVD+RW drive for an additional $160.

A useful external storage option to consider is the Iomega Zip 250 drive ($99), which lets you pack 250MB onto Zip disks for bringing digital presentations home from work or transporting other large files.

The Dimension chassis can be opened up without tools by depressing a button on the top and bottom of the tower (the bottom button requires you to lift up the system to reach it). It then folds open like the Apple G4, providing unobstructed access to all of the upgradeable components. These are well marked with bright green tabs--two tabs on each side of a drive bay let you slide drives in and out smoothly, while the green bar atop the PCI card slots pops up for tool-less card insertion. Sometimes closing the clamshell chassis can pinch wires or fingers, but it's a much appreciated design for any users who spend any amount of time inside their systems.

Audiophiles will want to upgrade the basic sound system that ships with the 4550. While Harmon/Kardon is a trusted name in speakers, their HK-395 three-speaker set doesn't do it for gaming or watching movies. The $80 upgrade to the Altec Lansing ADA745 4.1 speaker set still keeps the system affordable while providing surround sound to your games, music, and movies.

Windows XP Home comes pre-installed on the 4000 line, with an upgrade to the professional version available for an extra $60. While the WordPerfect Productivity Pack does include some useful applications, the $15 upgrade to the Microsoft Works Suite 2003 is a no-brainer (Microsoft Office XP Small Business can be had as well, but it's an additional $150).

Two front USB 2.0 ports and a front headphone jack keep you from having to crawl behind the system to connect peripherals and headphones--a flip open cover masks the ports when they're not in use. There are four more USB 2.0 ports on the rear of the system as well, so you won't run out of connectivity options quickly.

A network interface is included in the 4000 line, so you can connect to a broadband DSL or cable modem. (A 56K modem is optional.) Users without a current ISP will appreciate the six months of free AOL or Earthlink access included with the system.

Wireless options are available for the 4000 line, including a Logitech wireless keyboard and mouse combo ($65) or a wireless USB adapter to connect the 4550 to a wireless home network ($69).

While you can quickly run up the bill on Dell's configuration Web site, moderate upgrades can give you a powerful system for around $1500. This includes a 2.53GHz Pentium 4 with 512MB of RAM, the 4.1 speaker set, and a 17-inch flat panel monitor--quite an impressive PC for an equally pleasing price.

Pro: Powerful mid-range systems, functional and visually pleasing tower.

Con: Only two memory sockets.