Tested on 750Ti - 18.8 MH/s , but CPU usage is 100%. The older Nvidia miner reaches 23.5MH/s.
I haven't any view on AMD version

linux or windows ? In principle it is based on the latest algo (can you point me to what you were using before) ?
(the change I made shouldn't have any impact on hashrate)
Win 8.1 64bit. I compared with older skminer, It should be somewhere here on the thread (I'm not sure ).
EDIT: I found it on the thread , but the link no longer exists:
http://coinshield.io/binaries/miners/skminer_nvidia.rarEDIT2: the post is from 06 of November 2014
ok, I will have a look, however I was on the impression that I was using the latest.
Did you recompile it yourself to x64 ? This might affect the performance, for some reasons nvidia miners performs always better when compiled with x32