I didn't think any single Windows application could use more than 2GB... Or has 2000/XP lifted that restriction, without needing separate application image for NT systems? And remember that's virtual memory of 2GB, not just real memory. So Windows may have your system at ~6GB virtual already unless you overrode it. Sounds crazy but have you tried running P5 limited to <2GB (to keep it out of trouble). Say 1GB real, plus 960MB virtual?