(FORTUNE Magazine) – High technology in the workplace conjures up images of the swinging robot arms and blinding lasers that have lifted productivity on the factory floor. Technology has generally been slow to pay off for service companies. Nonetheless, security analysts have uncovered a promising group that use computers for order taking, inventory control, data processing, and market research. Investing in the most successful of these companies, they say, could mean a large serving of capital gains in the future. William Welty, head of equity research at San Francisco's Hambrecht & Quist investment banking firm, recommends buying the shares of high-tech service companies that are run by entrepreneurs and have a distinct competitive advantage, such as proprietary information or a vastly superior product. One such company, praised by shoppers and shareholders alike, is Lands' End, the mail-order seller of men's and women's sportswear in Dodgeville, Wisconsin. ''It is the premier retailer of its kind in America,'' says analyst Steven Ashley of Blunt Ellis & Loewi, a brokerage firm in Milwaukee. Lands' End uses terminals hooked up to IBM mainframes with proprietary software to fill orders quickly and accurately, as well as lasers that scan and sort merchandise. Ashley estimates the company will earn $1.05 per share in its fiscal year ending this month, up 44% from the 1987 fiscal year, and expects earnings to keep growing at a 20%-a-year clip. McKesson is a large San Francisco conglomerate that distributes nondurable consumer goods such as health and beauty aids and pharmaceuticals. It has a giant wine and liquor distributing subsidiary. Customers of these businesses order by computer. The company also owns 86% of PCS, a very profitable computer network under which members of employer-paid health plans use plastic cards to pay for prescriptions. Ram Capoor, an analyst with Morgan Stanley who recommends the stock, believes the sum value of McKesson's pieces is unrecognized by the market. The stock sells for 13 times his estimate of earnings per share in the fiscal year that ends in March. MTech, which is 80% owned by MCorp, the troubled Texas bank, is the nation's largest data processor for banks. ''It used to be that big banks did their data processing in-house, but with all the new products they offer that isn't as cost-effective,'' says Lisa Romeo of E.F. Hutton. Under a new agreement, MTech will take over some of the data processing for Manufacturers Hanover's correspondent banks. Romeo estimates the company's 1987 earnings at $1.20 a share, up 50% from 1986. Both Merrill, a financial printer and Information Resources, a market research firm, have had a rough time lately. Merrill, whose regional service centers across the country are linked electronically with headquarters in St. Paul, has seen its stock plunge below $4 from a 1987 high of $21. The reason: investor fears of a slowdown in security financings, which require reams of documents. Michael Hamilton of Piper Jaffray, a Minneapolis brokerage firm, recommends the stock for long-term investors. Earnings dipped to about 60 cents a share in 1987, he says, and should begin to grow in the second half of 1988 at a 15%-a-year tempo as financings pick up. Information Resources was set to merge with Dun & Bradstreet in November, but the stock fell after the Federal Trade Commission blocked the tie-up as anticompetitive. ''The company's computer market research system is far superior to anything else on the market,'' says Joseph Laird of Hambrecht & Quist, who is high on the stock.

CHART: THEIR COMPUTERS ATTRACT CUSTOMERS COMPANY REVENUES NET STOCK PRICE RECENT latest four INCOME RANGE PRICE quarters in millions last 12 months P/E multiple* in millions

McKesson $6,947.0 $89.0 $23.25-$39.625 $26.50 13.9

Lands' End $305.0 $19.6 $11.625-$30.25 $19.75 20.4

MTech $218.9 $13.1 $10.00-$27.50 $16.50 14.9

Information $107.0 $2.9 $8.00-$32.375 $11.00 Resources 42.3

Merrill $55.1 $3.4 $3.875-$21.00 $5.75 7.9

* Multiple based on earnings for the latest four quarters, exclusive of nonrecur ring items. CREDIT: NO CREDIT CAPTION:These companies are using high technology to increase productivity and profits. At Lands' End, a catalog retailer in Dodgeville, Wisconsin, workers punch orders into terminals. DESCRIPTION: See above.