Hey all.  I'm newbing it up still, and practicing with free trial VPS before I invest money into a mining rig.  The problem I keep having, is a declining hashrate. 

Some of the VPS I set up were clocking 5k and more the first time I connected them.  I had to close the session to restart my computer, and when I reconnected my hashrate fell in half.  Then the next time I had to close the session and start again, it feel even more.  Now my best performing VPS that was at 5k+ is now averaging around 0.56k.  This has happened with all of the 14 VPS' I have running right now.
 
Can anyone tell me why this happens and how I can fix it? 

Appreciate any help!