Hey guys, Thanks for answering my previous question. It's best to operate at stock. Now I have another query, Is it normal to see CPU Temp of about 75 C at stock (on full aida64 stress)?
If you are using the stock paste, and your ambient room temperature is 69 - 70 degrees Fahrenheit, then no. It should max at 65 - 66C with the Wraith Spire cooler, however, if your room is hot and you are seeing 75C, not much can be helped, at stock settings it's safe up to around 83C (based on when electro-migration happens) I'm not going to go in-depth with it here, but basically the heat can stretch the silicon in the CPU and damage the CPU DIE (the cores) by creating pockets that expand in the silicon due to the heat over time.
That happens on the stock settings at around 83C on full load (At 1.4v+ it can happen after extended use at 65C, and at 1.5v it can happen as low as 57 - 60C, although 1.5v has the potential to damage your CPU DIE outright, let alone on load, or at high temps.)
So generally you want your CPU below 60C, and below 1.3625v or so, it boosts higher than that for short periods of time to allow one core to boost higher than the rest, and that's fine, but running it like that 24/7 across all cores under load is dangerous, and will lessen the life of your processor.
If you want it to last a while, leave it at stock and run it as intended, the more expensive processors aren't just expensive to soak in money, they are hand picked from the bunch and tested, and very few meet the standards for running at those speeds at such low voltages, all Ryzen 7 1800x chips won the silicon lottery, and were lucky to do so, and since they don't have a humongous stock of silicon lottery winning chips, they sell them at a higher price to prevent from selling out of those chips all the time.
That being said, you seem to have a decent chip, but it's still lessening the life, or outright threatening it's lifespan if you run it at anything higher than stock, to keep it cooler, do the following:
Reapply a better thermal paste to the CPU.
Keep room temperature at or below 26C (for best performance keep it around 21C (69F)
Turn off "AMD Cool N' Quiet"
Set a custom fan curve to go to 100% fan usage at 63C, and 90% at 60C, etc, steep curve, but don't go below 60% fan usage at 40C, etc. Find a setup that works for you.
I know this is a lot of information, but it's a good read, and it will help you greatly, don't skip anything.