The system will randomly reboot with no warning or error message from windows after running quite stable for 2 years.
The only thing that seems to have an effect is to raise the voltage on CPU, right now i'm running 1.55v on the cpu and that seems to stabilize it.
The strange thing is that this behavior is most common when i boot the machine after it's been off for a while, like in the morning when it's been off all night.
Once the machine is up and running it seems to work fine, even under load. This tells me that it's not a heat issue since the cpu is never above 50 degrees when it boots.
CPU boots at around 40 degreess, typical idle is 50, full load is 70-75.
I've tried:
Replacing PSU
Memtest86, ram passes with no errors.
Adding a new after market cpu cooler (temp drop, no effect on issue)
Adding a case fan (temp drop, no effect on issue).
Updating bios & clearing CMOS - no effect.
The only thing that seems to work is to raise the voltage to dangerous levels. Does anyone have any idea what might cause this?
The system has been used a lot the past 2 years and it's been running fairly hot, could it be regular degradation causing the need for high voltage now?
Sounds like cpu power delivery problem on the motherboard. Capacitors on motherboard might been degraded over the time especially if it ran hot. Look for bulged caps if they are electrolyte type. If they are solid type then You eill not see it. I guess You will need to swap motherboard to check for sure