I think it would help to post you system specs
But anyway, you can try out this "mod"
http://www.subsim.com/radioroom/show...55&postcount=2
if that doesnt work/crashes your game, go into your nvidia/catylist control panel and set the max rendered frames to "2", thats what the mod does too, with the difference that the mod also let you set a fps limit
and for me it helped a lot to disable AA in SH5 and activate it via the control panel, i set it to 4 cause imo thats enough at 1680x1050 resolution
EDIT: put the mod (antilag) files just into your SH5 directory where the exe is