I wanted to use a yeast cake but its been sitting in a 80 degree garage for 2 weeks. Do you think I would still be able to use it. It smells fine but I dont want to waste ten gallons of beer just to save $7.
i would just get new yeast. 80 degrees under alcohol i would consider to be a harsh environment for yeast. i reuse yeast but save it into mason jars right after kegging and it goes into the fridge.
In that event, I agree with eastoak (and it kind of sounds like you already knew the answer when you asked the question) -- If you are at all worried about it, why not just err on the side of caution.
Unless you wanted to split the batch and do an experiment: 2nd gen vs 1st gen