Can any one help me about Mikrotik VPN Server.
I have
RouterOS 5.16 with level-6 key
xeon 3093MHz dual core machine. using multi cpu.
4GB ECC Ram but supported 2GB
3 intel giga lan cards.

i am using 96 lines firewall and pptp server.

When my pptp server cross upto 500 users and cpu use only 29%, why getting issue are
ping braking
slow browsing

what about speed to the server? (wan) bandwith enough?

I agree, it sounds like you are running out of bandwidth.