do i need to stress test when successful enter window after OC?
if yes, how long do i need to stress test?
mine is 6700k, AIO ID cooling 240, below is test result on xtu n realbench
xtu (benchmark)
4.6g@1.325 = result pass temp 86c (temp result in xtu app itself)
4.7@1.375 = result pass temp 93c (temp result in xtu app itself)

real bench (benchmark)
4.6g@1.325 = pass (temp hwdinfo 86c)
4.7@1.375 = pass (forgot)

I have run stress test using realbench 4.6g@1.325 for 1 hour, and it pass (before I install GC). then i try 4 hours test (after GC install) and go sleep. next morning, my pc was restart. So i dont know whether my OC is good or not. i use my pc 24/7 run at 50% load on CPU and RAM (16gb corsair lpx 3000). is something wrong with my setup?

another thing is, i'm consider to invest in custom water cooling, but i want to know, whether i can achieve below 80c when do benchmark or stress test? currently max temp around 86-88c on AIO cooling. please advise. thanks!