On both computers run exactly the same. I have also tried several webserver software and the type of the webserver had no influence on the speed of PHP scripts. The speed of HTML pages is excellent on both machines, the only problem is with PHP. The machine with Win98SE has only K6/350 CPU and 64MB and all the PHP scripts run here 5-6x quicker as on the machine with Win2000 (Celeron 466 or VIA-Cyrix 550 and 256MB, HDD with 7200). The only difference is, that on W2k runs the webserver as NT-service. So I mean the problem is about PHP configuration. I have also tried several versions of PHP (now I am running v4.0.6), but the result is always the same.