Page Loading Issues

Anyone out ther encountering intermittent loading problem? Sometimes my cscart will be unable to load up and shows only a blank screen and have to reload it.

I had cleared the statistics, optimized the database and also clear the cache and still facing the same problem.

I am currently running cscart v2.2.4 on VPS server.

My VPS server system information as follows:

CPU - 1.13 GHZ

RAM - 768 MB

Disk Space 30 GB

Bandwidth - 500 GB