Are CPU Renders bad news ?
glennblackphotos
Posts: 160
Are CPU renders bad news for your cpu Mac or Pc as the cpu gets hot ?
for example would a ten minute test render fry your cpu ?
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iMac user. Haven't given it a thought really, some of my still renders can take 15h or more, and when rendering to movie 24h is not uncommon.
I agree with @Sven Dullah. I do CPU renders on my windows laptop that can take a day or a few times two days to render and I have been for the last few years :)
I agree with @Sven Dullah. I do CPU renders on my windows laptop that can take a day or a few times two days to render and I have been for the last few years :)
And do you hear the fan running to cool the cpu ?
The CPU is heating not because you are rendering is heating because the cooling system is failing, the main reason is dust blocking the exit of hot air. Not fixing this condition will fry your CPU.
I clean my computer every other month with just compressed air, it is amazing the amount of dust that acummulates over time.
Not since I wore out the old one and replaced it with the new one :)
I suspect you replaced it with a faster one, isn't it?
No, I replaced like for like.
While I haven't researched failure rates, I've had all cores pegged at 100% for somewhere between one and two weeks straight, no problems. Many renders I do take many hours or overnight. 10 minutes is nothing. Of course your processor/case needs adequate cooling, whether that's already the default or you add a 3rd party cooling device, and you might want to evict the dust bunnies in your heat sink. At least some machines have a temperature sensor built in that can shut it down in the case of overheating. You'll loose your work, but not your hardware, with this option enabled, you could look for that.
They can be, just like they can be bad news for GPUs; the issue can be heat, which if inadequate cooled (lots of fans does NOT mean good cooling, it needs to be planned and implemented correctly), can result in a dead cpu/gpu sooner or later.
As others have said, make sure that you case is clean around the vents especially, and the fans and their vents are likewise clean.
Another component that should be a concern is the PSU; long and sustained use will push it to its limits in many off-the-shelf systems. So check out your PSU. (Rendering can kill powerful gaming systems, although it is pretty unusual.)
I can't see ten minutes and longer causing issues unless there are serious problems you are unaware of.
HWINFO64 is a good free monitoring tool, great fo watching temperatures of CPU
I use Bryce. I only ever render in Bryce, so I only ever make CPU renders I love Bryce but I think nearly everyone knows that well populated Bryce scenes can take a while to render.
I have never had a computer overheat.
You live in the mountains of Wales I thought: 50 below in high summer.
So this is really a hardware question, right?
The iMac I normally use for rendering is completely silent,which is nice, since I use it for audio recording to make a living. At home I have an old Macbook with 2Gb of RAM, one render (3DL) I made on it took a week, fan going full speed all the time, and it's still kicking LOL.
Heh We are all white today. But not as badly white as the last time (yet)
CPU's are designed to be used, even at full capacity. Computers that come prebuilt are designed with airflow solutions that when used correctly mean that you can render to your heart's content. However if you put things in front of the vents or allow too much dust to build up then that's when you get problems. It's actually pretty hard to damage a CPU, it's more likely you'll get crashes/instability and a shutdowns as the protection measures cut in.
Like others have pointed out your motherboard has temp sensors built in. You can download a utility like Speedfan, Ai Suite or MSI Afterburner and they will give you a temperature reading for your CPU and motherboard (and GPU possibly). You can even set it up to sound an alarm when your temp reaches a certain level, or even shut down automatically. Also, search online to see what your particular CPU's limit is. For most it's around 70°C but it varies.
As long as your cooling system is working ok, your CPU can run at full load for a few hours without damage. I mean, everything fails eventually, but it'll last until it becomes obsolete and you want to upgrade to something faster anyway. Over the years I've done plenty of gaming, rendering and distributed computing (donating CPU time for medical research) and I've never had a CPU fail. Hard drives on the other hand...
for CPU rendering I use RealTemp, because it monitor Cpu and Gpu, even alarms you when reaches a CPU's Max Temp possible.
Why do you use optix?
It's a speed booster for Iray.
I'd argue if your CPU heats up from rendering, something is wrong with your cooling system. I've rendered on both a FX 8350, and an i7 3770, and both are still running fine with pretty basic coolers. If rendering heats up your CPU, then everything else will too. Buy a better heatsink. However it doesn't hurt to check your shaders/lighting/materials and make sure your not needlessly making your scene too complex. I was at 5 minutes per frame which was not good for me, and reduced it to 1.5 minutes, just by cleaning up my scene, and using tricks to avoid over complicated back grounds. Regardless, in the case that a PC is overheating, the same could happen to a poorly ventilated GPU. In fact it's more likely to happen to a GPU then a CPU.
It's definately bad news, GPU or GPU and especially in a laptop. Eventually the exaggerated heating and cooling cycles will break a circuit in the board. That may not apply to the newest HW though as they are always lessening heat generate and improving quick heat disapation.
CPUs are designed to run 100% for months non-stop. As long as you have adequate cooling and it stays within recommended temperature ranges at all times, you'll be fine.
You would have to have really bad cooling for your CPU before a render or anything else that will max out the CPU usage would fry it. I have a Noctua NH-D15 and my CPU, which runs at 4.2 GHz does not go past 65C. WHen its done, the Noctua kicks the heat down super fast.
That's the heart of what's been bothering me for awhile. I switched to Macintosh computers a decade ago. My current 2013 27" iMac meets all my needs, except for DAZ Studio. I don't want to spend hours or days rendering one picture. It stifles my creativity.
The next logical step is to get a good PC computer just for DAZ Studio. Oh, but that costs money. I'm about ready to put aside all my DAZ Content for the long run. I have all my DAZ Content installed on a 3TB external drive, and have it backed up to another 3TB drive. I'll just disconnect the drive, and then pack it somewhere safe.
My CPU renders at about 85c while in cpu mode... My case and cooling aren't the greatest. However, I use GPU mode most of the time which I have set to max out at 79c.
My CPU/GPU/Motherboard idles between mid 50's ºC and they top out at the upper 80's ºC when rendering, which has taken anything up to 2 days, and it has been nearly every day for the past few years. I had to replace a worn out cooler fan that was making too much noise and it also sits on a two fan cooling mat which I bought last year, before that it sat on a tray, on a pillow, on my lap, basically because I was getting burn marks on my legs :) I found a lot of the heat comes from the two 8 GB memory modules.
I've managed to get an external Nvidia GPU working on my iMac running El Capitan. Unfortunately the setup isn't supported on macOS 10.13.
You can set the "Affinity" for DAZ, after it starts running, to ONLY use a set number of cores. Open task manager and go to the "Details" tab. That will have to be "set" every time you restart DAZ. Since you can't actually manage tempratures any other way, in most cases, that is a more realistic approach to heat-managament for the chip. (You can also set limits for the "maximum speed" of the CPU clock, in the power management settings. Though, some programs don't always obey "windows user settings", and windows can't always control "non-windows software". So that can be a shot in the dark, per program.)
Not using a CPU, degrades it... Using a CPU, degrades it faster... Using it a LOT, degrades it even faster... Pushing it to 100%, constantly, degrades it even faster...
At the end of the day, yes, rendering with your CPU will shorten the lifespan of the CPU. No matter how well you cool it. Sustaining a "safe maximum level of heat", is all a cooler is normally designed for. That translates into something like 10x-20x faster decayed life-span, when compared to "normal use", of the "expected lifespan". CPU's in normal use, tend to last about 10-20 years, depending on the company quality expectations. If you ran your CPU at 100%, 24 hours a day, 7 days a week, that 20 year life-span would be seen after 1-2 years. (Those are total speculative and rough estimates, based on reported findings from computer-centers who constantly run hardware to 100% of "specs", and some personal experience while doing bitcoin-mining, myself.)
However, adequate cooling will help reduce the natural decay of the chip. Hot things decay faster than cooler things. Heat was used to turn the silicon into a "loose state", so it could crystalize. It was "burned" into shape, to create a "series of circuits", which is the most perfect it will have ever been, after it cooled. Oxygen and heat, and time, will eventualy deform the silicon enough that it no-longer functions as it did, when it was first created. Thus, failing to operate, at some point.
P.S. Most people who actually "USE" computers, daily... Tend to get a new computer every two-three years, as software demands more processing power. Way before it is ready to die. (Thus the lower life-spans for consumer-grade hardware.) Data-centers tend to use hardware until it actually fails, completely. (Thus the longer life-spans for comercial hardware.)
P.P.S. Hardware rated for "life-support" and the military, like your cars computer that controls your anti-skid breaks, airbags, and heart-monitors... Those tend to have a 40-80 year expected life-span, with redundancy (A portion of the chip that never runs, unless a failure happens in the primary core). NASA has hardware rated for 100+ years, for use in space. Total overkill, but they will never use a consumer-grade CPU or hardware, out in space.