xīn / diàn / nǎo / yù / zhuāng / le / zhèng / bǎn / cāo / zuò / xì / tǒng / ， / bù / yòng / zì / jǐ / é / wài / ān / zhuāng / 。

新电脑预装了正版操作系统，不用自己额外安装。

The new computer has a preinstalled genuine operating system, so you don't need to install it separately.