OverDrive is designed to make overclocking your PC simple, and we found that it works well. You'll need to be sure you have the "Black Edition" of AMD's Phenom II chips, which come with an unlocked clock multiplier. To Dell's credit, all of the AMD chips available with the XPS 625 fit that bill.
Given the deviation in overclocking tolerances, we did not test out OverDrive on every component in this PC. The software is fairly powerful, though, letting you overclock things like the graphics card, the 16x PCI Express bus, as well as the HyperTransport multiplier. The software also monitors internal temperatures and provides a benchmarking suite for testing your changes.
We dialed the 3.0GHz Phenom chip in our review unit up to 3.3GHz by moving the clock multiplier to 16.5, and then set the software to test its stability overnight. The system passed with no trouble. As no two pieces of silicon are the same, your tests will vary, but we can say that we're happy with both the method and the reliability of overclocking on our test system. The OverDrive application also effectively replaces the Nvidia ESA software in the XPS 630 that plagued at least a handful of users with inaccurate temperature readings and mistakenly increased fan speeds.
As a complement to AMD OverDrive, you also get AMD Fusion, which acts like a software manager. It appears as a simple dial on your desktop. Turn it on before you launch a game, and it shuts down all of the extraneous applications and processes that sap performance. It comes with three presets, as well as a profile manager for creating your own settings. OverDrive is probably more useful of the two programs, as it's easy enough to manage your background processes by hand. Both of these are worthwhile value-adds, but neither is exclusive to Dell. You'd expect to find them the on the less expensive Maingear Dash referenced above, for example, which also offers overclockable Black Edition AMD chips.
Of the XPS 625's exclusive features, the 750-watt power supply and Alienware's fun-but-gimmicky AlienFX lighting software (change light colors, set lights to blink with new e-mail) are about all it can claim that truly set it apart. The Maingear Dash has only a 650-watt power supply, and the Gateway FX6800-01e has a paltry 500-watt PSU. The 750-watter in the Dell gives you plenty of headroom to add one or even two faster 3D cards, even after overclocking. You get less of a cushion in the Maingear, and basically none in the Gateway. That extra room may indeed provide more value. Of course, you have to shell out even more money to put it to use.
In addition to the power supply, Dell provides you with a fair number of slots and bays in the XPS 625 as well. You get two PCI Express graphics card slots, two standard PCI slots, and a 1x and 4x PCI Express slot for card expansion. That's a lot. We also admire the hard-drive layout, which features four bays facing outward, each with a removable plastic drive tray and the power and data cables smartly lined up at the ready for expanded internal storage. The external ports feature the standard current stuff, including plenty of USB ports, an eSATA input, and optical digital audio output. Sadly, the $1,499 you pay for this system doesn't get you a media card reader, a common feature of even $350 budget PCs.
Dell's service-and-support policies remain as robust as other top-tier vendors. You get 24-7 toll-free phone support with the XPS 625, as well as a year of parts-and-labor coverage, with plenty of options to add additional coverage should you care to pay for it. Online resources are plenty, with FAQs, links to driver downloads, as well as Dell's ID-based system specific help.
Find out more about how we test desktop systems.
Windows Vista Home Premium 64-bit; 2.83GHz Intel Core 2 Quad Q9550; 8GB 800MHz DDR2 SDRAM; 512MB Nvidia GeForce 9800 GTX graphics card; (3) 640GB 7,200rpm Western Digital hard drives
Windows Vista Home Premium 64-bit; 3.4GHz Intel Core 2 Quad Q9450 (overclocked); 4GB 1,600MHz DDR3 SDRAM; 512MB Nvidia GeForce 9800 GTX graphics card; (2) 500GB 7,200 rpm Western Digital hard drives; 150GB 10,000 rpm Western Digital hard drive
Dell XPS 625
Windows Vista Home Premium 64-bit; 3.0GHz AMD Phenom II X4 940 Black Edition; 6GB 800MHz DDR2 SDRAM; 512MB ATI Radeon HD 4850 graphics card; 500GB 7,200rpm Western Digital hard drive
Windows Vista Home Premium SP1 (64-bit); 2.66GHz Intel Core i7-920; 3GB 1,066MHz DDR3 SDRAM; 512MB ATI Radeon HD 4850 graphics card; 750GB Western Digital 10,000rpm hard drive
Velocity Micro Edge Z55
Windows Vista Home Premium SP1 (64-bit); 3.0GHz Intel Core i7-920 (overclocked); 6GB 1,066MHz DDR3 SDRAM; (2) 512MB ATI Radeon HD 4870 graphics cards; 750GB 7,200 rpm Hitachi hard drive