I published a new release. 1.16.
It is now possible to specify freely a grid size and increase performance on certain GPU.

C:\C++\VanitySearch\x64\Release>VanitySearch.exe -t 0 -gpu 1TestMe
VanitySearch v1.16
Difficulty: 888446610539
Search: 1TestMe [Compressed]
Start Tue Jan  7 09:25:30 2020
Base Key: 2AC862CEC11BB2E15C5D864CEF26D3E0640BEA49DA58C4E96F1339B84E466C78
Number of CPU thread: 0
GPU: GPU #0 GeForce GTX 1050 Ti (6x128 cores) Grid(48x128)
[221.77 Mkey/s][GPU 221.77 Mkey/s][Total 2^30.72][Prob 0.2%][50% in 00:46:08][Found 0]

C:\C++\VanitySearch\x64\Release>VanitySearch.exe -t 0 -gpu -g 48,256 1TestMe
VanitySearch v1.16
Difficulty: 888446610539
Search: 1TestMe [Compressed]
Start Tue Jan  7 09:25:52 2020
Base Key: CB77C0255E5A334DCFA5B8788EB0FF6A04EBE360AA13A4D17A114E07EADCCD9F
Number of CPU thread: 0
GPU: GPU #0 GeForce GTX 1050 Ti (6x128 cores) Grid(48x256)
[271.78 Mkey/s][GPU 271.78 Mkey/s][Total 2^31.34][Prob 0.3%][50% in 00:37:35][Found 0]