Yeah 80 is fine. Mine run in the 60s and 70s for max temp in the winter, 70s and 80s in the summer.
It's probably a good idea to give them a cleaning though, just take both front and rear fan plates off and hit it with a vacuum and compressed air if you have it. After months or years of running tons of air through at fairly high speed, they collect garbage, and since the temperature of every chip isn't monitored you can run into issues eventually. I've been repairing miners for my host, and so far all the ones I've looked at have had some level of blocked heatsinks. Mostly dead insects.