I like to do multiple video renders in Sony Vegas for up to 3-4 hours. I usually render up to 10-12 videos at once. The CPU usage is always 100% for 3-4 hours. Is it safe to have your CPU under full load and the CPU usage at 100% for 3-4 hours?
Also, I worry about temperatures, I'm doing a huge render right now and my CPU has been at 54c for over 2 hours, that seems normal to me since the CPU is using all of its cores. What are normal temperatures at full loads? What are temps that will fry my CPU?
I have the AMD 965 3.4 GHz and I use the stock cooler. Right now, my CPU has been at full usage for 2:15 minutes...
Im not going to comment too much, cause im really not an expert but im sure you can stop worrying 54c isnt bad at all ,if it was in the high 90s you might have cause to worry, for example my current Q8200 has been running A LOT over about 2-3 years and gets to 85-90 while gaming and its still going strong but anyway, ill let someone else with more experiance answer this a better
i know, when i got my current system (prebuilt) i knew nothing about components/temps etc, the case is basicly just an oven, only has 1 fan at the back, stock intel cooler on the cpu. and it had been going for a good 2 years by the time i checked the temps, so i guess ive just gotten really lucky that it hasnt died. and i was exaggurating a bit on the temps, its late here and im tired regardless there a hell of a lot higher than yours
the truth is usage doesn't really matter all that much technically if you could render 200 videos at once and still keep safe temps you would be fine keep in mind that CPU's are meant to work at load some times for years even as long as you at a safe temp there should not be any degradation.
You can do whatever you want in terms of usage so long as you keep your temps in safe limits.
Overclocking kinda would throw a wrench into that, but it's still basically the same. Safe voltages and temps are what matters there. If you're rendering that many videos, you should OC a bit. Most 965's will hit 4.0GHz without much trouble. That'll save you 40 minutes on encoding time (if you're doing it for 4 hours). If you OC, you really have to burn it in to watch temps and will likely need an aftermarket cooler.
Think about it this way there are servers out there with CPU's of fairly similar build quality to personal ones that run 24/7 at 100% all year long for years at a time. And to what dalauder said OC really takes durability to a level we cant predict you can knock up your clock 10% and do no damage and push it 2% more and burn it out in some cases. Iv seen people pushing up there OC in steps with full stability get cocky take a decent jump and totally burn out there CPU. OCing can be fun but don't start unless you have a decent understanding of what your doing.
Overclocking: I agree that you shouldn't take OC'ing too lightly. But it's still about the voltages you have set.
You can't fry your CPU without overvoltaging or overheating it. You can set custom bios settings to make it so your motherboard won't post though--especially if you overclock doing big jumps. You could get cocky and burn your CPU out if you're careless, but that takes A LOT of carelessness. So long as you set voltages within spec and you watch your temps, you won't permanently damage anything more than your Windows installation (due to improper shutdowns if you're very unlucky).
Now in terms of stability--it takes some effort to make sure an OC is stable. But after you've tested it, it's as stable as a stock system if done properly.
Back to your original question: You're not hurting your system running it at 100% for 10 hours at 55C (but your power bill will feel it).
As everyone keeps telling you, as long as the temps are within the safe range, which they are, your CPU will more than likely outlive you no matter how much work it is doing. This is not like an auto engine where use means wear, it's an electronic transistor with no moving parts, it doesn't "wear out" in a sense like you are maybe thinking.