What really happens to a cpu that locks up...?

[Bartman39]

What I`m asking may need to be in the "highly technical" forum but will try here first...

What I mean is when a PC locks up because of to high of and overclock (say when running a benchmark or...?) and it just freezes what exactly happens...? And does it damage the processor to any degree...? (meaning if left this way for a period of time... 1min-1hour...?)

Do you get a thermal runaway...? Or does it just shutdown...?

A good semi-technical answer would be great...
thanks...

 

[Drsignguy]

Good question, I would really like to know myself.

 

[ChampionAtTufshop]

i dont think theres anything "bad" happening.....
apart from ahving juice run thru cpu for no reason lol....but that probabaly wont do much harm anyways

what happens, from speculatoin on my part, is the cpu cant figure out wtf to do with a 1 or 0 (cant tell what is waht maybe) and just stops lol....
probably not correct, but its a bump in anycase haha

 

[Syndicate]

I would imagine that if it managed to get into whatever benchmark you are running you couldnt have been running it any sort of an insane voltage or anything and therefor you wouldnt damage the proc. while it was sitting there locked. I am pretty sure that when it locks the process stops and you wouldnt be at 100% cpu utilization and therefor not overheating your cpu. But if you did something insane like ran your pretty XP 1700+ at 2.0v and got into a bench of 3DMark and it hung and you left it hung for hours....running the cpu at 2.0v for that long would probably damage it.. Anyway point is watch the benchmark unless you're just trying something a tad bit higher than its probably a safe all night stability check =)

 

[jiffylube1024]

Well if you think about it, what does increasing the voltage do? Increase the signal strength and clarity of the electric impulses in the CPU. A high operating frequency, in turn, degrades the signal strength for a given voltage (ie overclocking at default voltage).

This doesn't answer your question, but it is a way of thinking of how overclocking works.

Now for crashing, similar to an overzealous overclock, the CPU speed or voltage are too high to run reliably and the CPU sends muddled information to the OS which the OS can't understand. The pipeline stops altogether and the system crashes. This is just something I pulled out of my @$$, but maybe it's close to what happens in a hardware crash.

 

[Alphazero]

The CPU generates errors, and so the OS / software can't run properly, and so they get stuck.