Here are a few alternatives now for you to mine with X3.

Bytecoin BCN

URL: stratum+tcp://bcn.superpools.online:9999
Worker: your wallet address (optionally .DIFF+PaymentID for exchange)
Pawword: x

DigitalNote XDN

URL: stratum+tcp://xdn.superpools.online:9999
Worker: your wallet address (optionally .DIFF+PaymentID for exchange)
Pawword: x

Newton NCP

URL: stratum+tcp://ncp.superpools.online:9999
Worker: your wallet address (optionally .DIFF+PaymentID for exchange)
Pawword: x

B2b

URL: stratum+tcp://b2b.superpools.online:9999
Worker: your wallet address (optionally .DIFF+PaymentID for exchange)
Pawword: x

Karbo KRB

URL: stratum+tcp://krb.superpools.online:9999
Worker: your wallet address (optionally .DIFF+PaymentID for exchange)
Pawword: x