Top 30 in CS major. I would say No, 3.20 just too low. Most of them C- is the lowest grade you can have for individual class, but that 1.77 is about C- which is minimum requirement, just meet the minimum requirement it just put you in the hole. Sorry to say, about LoR doesn't help much, most of the university, if you have LoR from who graduate from that institution just make them give you an extra person to read your essay, it doesn't increase your chance or anything.