B die ram is most stable at ideal low 20c range, 20-30 is ideal if you can get it, 30-40 is acceptable but you won't be able to push it as hard, over 40 is to be avoided especially if you are pushing the sticks past their XMP. I start to throw errors around 45c.
I'm going to see if I can replace the thermal pads under my neos heatspreaders with 13w/mk, hopefully lower temps, every c matters, literally.
I'm lucky in my case because its a sandwich layout so no gpu heat onto ram, and cpu is liquid cooled with radiator exhausting through the top of the case and intakes at the bottom. I imagine it's possible for you to figure out how to get cooler air to the ram dimms by sorting out those two heat sources.
If you are getting temps of 65c on your ram that's unacceptable and you should be seriously worried about os corruption with the amount of errors ram will throw at those temps..