THROUGHOUT the 1980s, Apple Computer appeared immune to anything vaguely resembling the PC market. Owning and operating your system obviously has its advantages - just ask Microsoft. But in the past three years or so, Apple has been forced to steadily reduce pricing on its flagship Macintosh range in direct relation to the fortunes of the ''price wars'' being fought in the IBM-compatible personal computer world. And with the PC war getting bloodier month by month, Apple has increasingly found itself drawn into the fray. In a bid to protect marketshare (and, in some quarters, to enlarge it) and improve its competitive position against IBM-compatible personal computers, the company today announced another round of price reductions on its Macintosh desktop and portable computers, as well as on peripheral devices such as CD-ROM drives and monitors. Apple Far East managing director William James played down the significance of the price war as a reason for tumbling Macintosh prices, preferring to put the price reductions down to internal saving on per-unit costs within Apple. Mr James said Far East customers were benefitting from a recent global manufacturing restructure. Since February, the company's Singapore production plant has supplied the region with almost all Apple products where previously it had produced low-end Macintosh and peripheral products - a cost-reducing move. Mr James also points to falling component costs and higher sales volumes as the basis for price reductions. Apple's marketing people talk of ''compelling prices'' and ''affordability'' as key to sales growth. In this they have been spectacularly successful, with unit volumes in the Far East up by 35 per cent in its fiscal first six months. Unfortunately, the war can be won and lost on margins as much as volume. Despite Apple's explosive sales growth, globally it has lost marketshare to the instigators of the current round of PC industry price fighting, IBM and Compaq. The squeeze is definitely on Apple, then, which is great news for users (and potential users it seems - the company says more than half the buyers of its entry-level Macintosh machines are both new Apple customers and first-time computer users). Some of the biggest price reductions announced yesterday were on the PowerBook - with cuts of between 15 per cent and 22 per cent. Macintosh desktop prices tumbled by up to 16 per cent at the low-end to between three and eight per cent at the high-end. CD-ROM drive prices were chopped by up to 43 per cent. And there appears to be no end in sight to the reductions. Key component prices continue to fall - dramatically in the case of screens and disk drives - and on-going miniaturisation reduces production costs. Prices would continue to fall until the end of the year, Mr James said, with promises of further reductions on PowerBook, which would be manufactured in Singapore by early next year. With its pricing announcements, Apple also launched two new PowerBook models yesterday; the 180c, which brings active matrix colour screens to the top of the line, and the 145B, which reduces the PowerBook entry level price by about 25 per cent.