Hi Did install the trial version on a clean Win 7. Performance is very bad, all in all hardly more than 10% of CPU power is used, all tasks are extremly slow (stacking, convolution ...) My, PC being a i7, there are 8 virtual CPU's of which Maxim only uses 4 at all - and those four with very very low performance. RAM is 16G - hardly 10% is in use. HD has plenty of free space. Switching into XP compatibility mode has no effect whatsoever Other software I have no troubles with. Any ideas? Thanks!