I don't know. I'm running Apache Webserver with PHP 4.2.2 and MySQL 4.0 beta on 4 machines running Win XP Pro, Win 98 2nd Edition, Win ME, and Win 95 on them. I'm running 95 on a big, fat 10-year old laptop that only holds 24 megs of RAM. Apache still runs fine and so does MySQL and PHP.
---†om