what can I do to stop it
I have no evidence
the hacker's address is 0xEEBbC9888fD8Ec5dFC267a915664780c8fa66426
My address is 0xd125a58b966dc8bdf10489fd910ca929934a0dbc
It happened in Jun 6th
I guess I download a virus altcoin wallet and the hacker found my private key in my desktop
There could be some factors, not only just a downloaded virus in your computer.
If you were using private key to unlock your eth wallet, you might be have been phished.
Unfortunately you cannot do anything of it, once the balance sent, it cannot be reversed.