thank you so much for your response and help, I really appreciate it.
Don't worry, we are here to help each other
One thing I did not understand, is what it means to put the rest in stock. Does it mean don't put any memory voltage and memory control voltage fields?
Exactly, because your overclock is unstable.If you try to modify all the settings at the same time, it's a mess to find which setting is the problem, so you leave voltages at stock and only modify the clocks first
Tonight I will try to do as you say, set core clock to 1300, put memory clock at 850 and the fan on 80%. and if it works I will increase the clock until it stops working right ?
Yes, right, you start with 850, and then 875, then 900, 925...until crashes and you'll see the limit, and you'll use the last stable clock