I've not had a single man patronise me
Lucky you. My favourite one was, "You can think logically because you don't have enough female hormones." But even the ones who comment on it being unusual to see a woman in the datacentre and things like that, it still emphasises that I am different and not their version of "normal". (Not surprised - in two decades, I've only ever dealt with two female field engineers from vendor support.)
Most men are normal and respectful, but I've certainly heard objectifying talk - they don't all talk about their wives respectfully. When I've pulled them up on it, I've been told, "You don't count, you're one of us." That still doesn't make it okay to objectify any other women.
I think it can depend partly on which area of tech you're in. Unix and networks techies are generally more sexist than those in development, customer support, project management and so on, although there are individuals in all areas which will be away from the norm to one side or another.
I saw Gina Rippon speak about 10 days back - she was very good, and the main them of the talk was that there's no real difference between male and female brains. There are differences in size - but not in performance.