I couldn't resist the price cuts, and just replaced my AMD 3800 dual-core 2 GHz processor with the 4800 2.5 GHz model, along with AMD's stock heatsink-fan assembly. This is a new PC that I built two months ago for rendering with Poser 7 SR1.1 on Windows XP x64, using an ABit NF-M2 nView motherboard with 2 GB of RAM.

I installed the new processor-heatsink-fan assembly and ran "CPU Test" for two hours with no errors this morning. Then I started rendering more sequential images for an animation I'm working on. About ten minutes later, I heard the alert bell sounding from the next room and rushed back, fearful of the worst.

Happily, there was no smoke, not even an error message on screen, but the bell didn't stop until I clicked Poser's Cancel button. I found that the BIOS default rings the alert if the core reaches 80 C, and shuts things down completely at 90 C. That's hot!

I underclocked the processor from 2.5 to 2.0 GHz a few hours ago, and it is still happily rendering frames as I write this message on my old backup computer. I know that rendering puts quite a load on a CPU, and I've read that AMD processors tend to run warm, but I'm guessing that this processor-heatsink-fan assembly is defective, and I'm planning to return it.

Has anyone else here had trouble with overheating their PC while rendering?

Thanks,
Ricky

Nada mate I'm running close to what you have. I have a 3800 dual core though but run with the stock AMD H/S fan. If you have enough colling for your case then I'd go with a bad H/S and fan. I know someone will come in here and bust about using stock H/S and fans but I have on all my systems and never had overheating. But as for me I beleive very much in case cooling without it having the top end H/S and fans don't mean a thing.

Attached Link: AMD ID Chart

Poser is hard on any CPU.  I do encounter reboots from poser(6), when over heating "Shutdown/reboot". To let you know, Intel chips run hotter than AMD. I would look into a good CPU fans for your chip. I am in for a new fan as well. I know you can underclock CPU's, but that is not the best thing to do, when it comes to logic gates, and frequencies. I do not underclock/overclock CPUs. Can shorten the life span, and they do not go well together when messed around with. I would use em the way they are ment to be used, even on Graphic cards. All would function better.  

This is my favorite AMD chart. Helps me identify a lot, when I build computers.

Also cooling in the case helps with the temp for the CPU.

Hrm. Your best bet would likely be to make sure that the following are true: 1) you're not overclocking the thing (even accidentally) 2) make sure the heatsink has just enough thermal goop between it and the CPU (not too much, not too little), and that the heatsink is seated correctly. 3) that the serial number on the CPU itself matches the serial number of the model, rated speed, and rated voltage. Grey-market stuff is notorious for mis-labelling, and it can wind up anywhere. Otherwise, you can consider water-cooling (not likely to help, since this sounds like a defective processor), or to simply return it and get one that works. HTH a little, /P

Noticing from the ID chart, I am surprised your CPU didn't get shot (burned out), from what you have shown in temp compared to the AMD CPU Id chart which shows 65 Degrees C. Something is not right.

The stock fans are almost always garbage.  Get a good Zalman cooler and your problem will probably be solved.  IMO you shouldn't even bother replacing the stock fan, just get one that's worthwhile.  The CPU test you ran probably did not hit both cores, and didn't properly heat it up.

The stock fans are good enough, you just need to make sure that the heat gets out of the casing...

What Dizzi said. I've seen folks buy those high end heat sink fans only to install them into a case with crap cooling you've got to get the heat out of your case. If not then installing a super turbine of a H/S fan is useless.

I also go for checking out how much thermo compound you have between the CPU and the heat sink.
Checking the rating and compatiblity of the CPU to the MB and PSU and all that good stuff.

Check your case cooling

Run a test that will hit both cores.