Drupal 6 admin is slow slow and slow on localhost

I just install Drupal 6 and found this is slow on admin site if I compare Drupal 5.

Detail:
OS: Windows Vistra
Web Server: Apache Appserv

I found many solution to solve this problem.

1. to modify hosts file in windows\system32\drivers\etc\hosts
from
:1 localhost
to
#:1 localhost

2. my solution to try is easy way
change URL (localhost to IP)
from
http://localhost/drupal6
to
http://127.0.0.1/drupal6
Speed come back again!!!!