to park the hard drive heads when the computer was to be moved. Most models also came with a word processing program developed by Leading Edge titled Leading Edge Word Processor, commonly referred to by its acronym 'LEWP'. To support the onboard real-time clock, a special driver must be loaded at boot in 'CONFIG.SYS', 'clock.sys', or 'clkdvr.sys' The computer supports the Microsoft Windows operating system up to version 3.0, as it is the last version of Windows to support Real Mode. Significance Dataquest estimated that the Model D won 1% of the American home-computer market in 1986, its first year of availability. The Model D was the first Korean-made PC to be sold in the United States, and at the time of its introduction, it undercut the price of similar IBM PC compatibles by $500. The $1,495 list price was the lowest of seven compatibles with comparable configurations in a September 1985 InfoWorld chart, and under half the price of the $2,820 IBM PC. Along with the Tandy 1000 and Epson Equity series, the Model D was one of the first IBM PC compatible computers to become popular for home use, due to its low price and good reviews. Many home-oriented software packages for the PC specifically cited the Model D along with the Tandy and Epson models as compatible hardware. Leading Edge was Phoenix Technologies's first customer for its IBM-compatible BIOS, and the Model D was one of the first PCs on the market to use the Phoenix BIOS. Although advertised as 100% IBM compatible, letters published in the January 13, 1986 issue of InfoWorld identified compatibility issues with several popular software packages and aftermarket hard drives. Syndicated newspaper columnists T. R. Reid and Michael Schrage, writing in April 1986, predicted that the popularity of the Model D would lead to hardware and software vendors specifically testing for compatibility. In spite of these early reports, the Model D sold well. In early 1987, Daewoo was producing 13,000 units per month and failing to keep up with demand. As a result, buyers waited 2–8 weeks before taking delivery. Reception PC Magazine in October 1985 called the Model D "the clear winner" among six inexpensive PC compatibles it tested. The review noted the computer's many included hardware features, and concluded that it "may represent the next generation of personal computing: about as compact as full IBM hardware compatibility allows, full featured,