Apparently, the altminer.net pool made a special port for GBX mining. Try port: 10000.
I am using it and it is working fine:
Based on pooler cpuminer 2.3.2 and the tpruvot@github fork
CUDA support by Christian Buchner, Christian H. and DJM34
Includes optimizations implemented by sp-hash, klaust, tpruvot and tsiv.
[2017-12-07 00:19:51] Starting Stratum on stratum+tcp://eu1.altminer.net:10000
[2017-12-07 00:19:51] NVML GPU monitoring enabled.
[2017-12-07 00:19:51] 2 miner threads started, using 'neoscrypt' algorithm.
[2017-12-07 00:19:51] GPU #0: waiting for data
[2017-12-07 00:19:51] GPU #1: waiting for data
[2017-12-07 00:19:51] Stratum difficulty set to 64
[2017-12-07 00:19:51] eu1.altminer.net:10000 neoscrypt block 10476
[2017-12-07 00:19:59] eu1.altminer.net:10000 neoscrypt block 10476
[2017-12-07 00:19:59] GPU #0: Gigabyte GTX 1060 3GB, 702.16 kH/s
[2017-12-07 00:19:59] GPU #1: Gigabyte GTX 1060 3GB, 695.14 kH/s
[2017-12-07 00:20:00] GPU #0: Gigabyte GTX 1060 3GB, 699.74 kH/s
[2017-12-07 00:20:00] accepted: 1/1 (100.00%), 1394.88 kH/s yay!!!
[2017-12-07 00:20:01] GPU #1: Gigabyte GTX 1060 3GB, 688.48 kH/s
[2017-12-07 00:20:01] accepted: 2/2 (100.00%), 1391.55 kH/s yay!!!
[2017-12-07 00:20:03] GPU #1: Gigabyte GTX 1060 3GB, 692.80 kH/s
[2017-12-07 00:20:03] accepted: 3/3 (100.00%), 1391.88 kH/s yay!!!
[2017-12-07 00:20:06] GPU #0: Gigabyte GTX 1060 3GB, 699.32 kH/s
[2017-12-07 00:20:06] accepted: 4/4 (100.00%), 1391.67 kH/s yay!!!
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