Hard drive defragmentation can help your company keep costs down and defer expensive hardware upgrades in the Windows NT and 2000 environments. Fragmentation occurs when files are updated often?new data is stored in any free space, which may be noncontiguous. Fragmented files require extra head movement in reading, so they take significantly longer to access than normal, according to "Disk Defragmentation: Hidden Gold for the Enterprise," a study by Framingham, Mass.-based IDC (a sister company to CIO\u2019s publisher, CXO Media). But use of defragmentation software can help avoid system delays and unresponsiveness that translate into lost productivity and frustration.IDC\u2019s study and previous studies by National Software Testing Laboratories, an independent hardware and software testing organization based in Conshohocken, Pa., show that a defragmented disk can increase overall system performance from 20 percent to 80 percent under Windows NT, with even greater savings on Windows 2000.Some popular tools include Diskeeper from Executive Software International and PerfectDisk 2000 from Raxco Software. Vadim Eijvertine, an assistant vice president in the security division of New York City-based Citibank, says everyone in his division has begun using Diskeeper with significant system improvements. "Before we started defragmenting regularly, the computers would hang up often; some would hang indefinitely on certain applications," he says. "Now my computer responds about 20 percent faster and lets me keep more windows open at the same time without hanging up." Defragmenting costs significantly less than prematurely upgrading hardware. For 1,000 workstations and 10 servers, hardware upgrades would cost $3.2 million; the cost of defragmentation software plus associated IT labor is just $27,710, according to the IDC study.