These links are helpful:
Manage your Database Size
If you’re using tens of millions of hands in your database you are much more likely to run into issues. We don’t condone datamining, but if you are doing it, you must be sure to actively maintain your database and not let it grow out of control. If your database is getting very large and your HM2/NC is getting slower, try creating a new database in HM2 and just import the newer hands that you need. It should help immensely. Also it may help you get better reads on your opponents because you are getting rid of old data that may not be accurate for the player any longer.
Delete packages and definitions that you no longer use from NoteCaddy
The more definitions you have active in your NoteCaddy, means the more data that is trying to get loaded from your database, leading to lag. Remove unneeded definitions by going into NoteCaddy and use shift+click to highlight definitions you don’t need any longer. Right-click on one of the selected definitions and choose “Make Inactive”.
If you still have troubles, and you’re using NCE 3.0 PRO, you should consider switching to NCE 3.0.
Please contact us if you have any troubles with the steps in the links, or if you have any further questions.