PC hardware forum: monitor shaking Problem

hey I need your help:) (my english isn't so good but I you will understand me)
my monitor is shaking so much
it start after I reset the bios setting (defualt) and cleaned the ventilator of the cpu and put mx-2 (Thermal Compound) because the cpu reach to temperature of 60c (now it's 45)

the screen is shaking so much (not only in the windows , in the bios screen too (the black screen that appear before the windows is strating)


I changed the monitor hertz to 75 (it was 60) and it's work better but still shaking.
After I changed the resulotion to 800*600 ,it's work good , but still shaking so much in the bios screen (but I want use it 1024 * 768)


What is the problem?
monitor problem? (is not a monitor problem (I conected it to my laptop (another computer) and it's work perfectly.)
drivers? (I dont think so , it's shake in the black screen, that appear before the windows is starting)
temperature ? (the cpu is 45c now , and the motherboard is 35c-40c)


I have:
samsung lcd 17 inch monitor , and onboard display adapter (built-in on Asus motherboard)



P.S. (another problem)
the ventilator of the cpu are noisy because is work on 100% speed all the time ,
I Changed it with "speedfans" software to 50% speed and it's less noisy , the temperure is 45c and , but it's fine , the 100% speed is very noisy), but it's reset all the time to 100% speed again when I restart the pc , so I change it to 55% again and again, so what can I do??? (it's disable at the smart\auto speed fans, on the bios menu, if I put it as able , it's noisy too).