[syslog-ng] syslog-ng performance question

Hi ! I have to set up central logging server for approx. 80 machines using syslog-ng with SQL DB (MySQL or PostgreSQL or Oracle db system). It is a homogeneous system so i will have to log traffic from syslog-ng-friendly servers. I will use syslog and syslog-ng for unix clients and Snare Agent or NTsyslog for windows clients. I want to use unix DB server. I want to log "normal" and sometimes debug informations. I need to choose hardware for DB server and DB server. Thanks for your help ! ps. questions are desirable :-) -- greetz Daniel