The HP Compaq 4000 Pro SFF (which stands for Small Form Factor) is a compact-size budget desktop with decent performance and eight USB ports.

Our review model, priced at $650 as of July 25, 2011, packed a Pentium Dual-Core E5800 processor running at 3.2GHz, 2GB of installed RAM (upgradable to 8GB), a 250GB hard drive, and a 64-bit version of Windows 7 Home Premium.

In PCWorld's World Bench 6 benchmark tests, the Compaq 4000 Pro SFF earned a score of 110, an acceptable mark for a budget desktop PC; the current tenth-place budget desktop PC, the Acer Aspire X3400, picked up a mark of 104, while the ninth-ranked PC, the HP Pavilion p6640f, collected a 119.

On PCWorld's Unreal Tournament 3 graphics tests, the Compaq 4000 Pro SFF barely reached a double-digit frame rate, at 10.5 frames per second--and that's at medium quality settings and a screen resolution of 1024 by 768 pixels. At those same settings, most budget PCs don't do much better, though--the HP Pavilion p6640f, for example, managed only a still-unplayable 21.9 fps.

The Compaq 4000 Pro SFF's compact chassis is plain and unassuming. The front includes vertical (or horizontal, if the machine is lying on its side) venting, but otherwise it's just matte black plastic. The side (or top) is emblazoned with HP's logo. On the front of the machine are four USB ports, headphone and microphone jacks, the power button, and access to the DVD-RW drive.

The back of the PC features offers four more USB ports, gigabit ethernet, VGA, DVI, a serial port, PS/2 ports for both mouse and keyboard (which the included peripherals use, sensibly enough), and line-in and line-out jacks.

Both the mouse and the keyboard are black with silver accents. They are comfortable to use, though not especially sleek or modern. The keyboard's regular, raised soft-touch keys are quiet and give good feedback. The mouse adopts an ergonomic three-button optical design.

Though the Compaq 4000 Pro SFF's case is compact, it provides a decent amount of room for internal expansion. Opening the case involves loosening one thumbscrew and then lifting the side smoothly off. Inside you'll find one open PCIe x16 slot, one open PCIe x1 slot, two open PCI slots, and one open RAM slot; the RAM is upgradable to 8GB.

The HP Compaq 4000 Pro SFF, like many other budget machines, has a plain chassis devoid of fancy features. Still, for the price, it's a solid performer with a reasonable array of port options. And because it's a bare-bones system, you're spared the bloatware that comes with higher-end machines.