I've read and been told not to exceed 55C and that the processors are temp sensitive. Which is hard for me to stomach considering i was wanting to hit 3.8-4.0 on air. AMD's page says 62C though just like my intel products that i've owned. Below 55 on air seems a bit tough unless ambient temps are just that cold. Right now i'm currently cooling with a zalman 9500.
Before i set memory to the timings they're at now, i had 12 hrs prime95 (Min FFT:2096 Max: 4096/ Memory: 6000mb] and 5rds of IBT.
Set memory to the timings they're at in my sig ran memtest and passed. So i proceeded to run IBT 10 rds on maximum instead of 5. And i failed the 8th round. It could be that Cpu is just unstable and might need a slight increase. But if the processor is temp sensitive then i'm also considering heat being the cause, Load temps were 58C. Rather high but ambient temp was 81F which is hot for that room. Currently re-running the test at 71F, load temp is 54C. It's much faster this time around.
62c is max, i try not to go over 58c
you should have no problem hitting 3.8.
have you tried bumping the vcore up?
you should be safe with anything 1.5 and under.
i ran my 965 at 4.0 on 1.488 vcore 24/7.
i say give it a shot