is it possible to obtain a long term visa, if one is married to a thai,and is over seventy years old...

and are the conditions different to a normal retirement visa?

I don't know of any magic at age 70 so you would have the option of either a retirement type extension of stay with 800k or the support Thai wife extension at 400k.

Or if you are thinking about one year multi entry visa that should be easily obtained in Penang but you then have to make visa runs every 90 days - but there would not be any bank account/pension requirement.