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Message: [QUOTE="Paul, post: 11615450"] It probably runs at 38 degrees at idle. To characterize cooling solutions, you load the CPU up with software to run. Prime95 can run the processor at 100% load. The processor could run hotter that way, and that is how you determine whether it is in trouble or not, while it is at 100% loading. Heatsinks are rated according to a number of things. The simplest characterization is called "theta_R" and would be valid at one fan speed (like full speed). To work an example: Say the room temperature is 25C. Now, say the inside of the computer case is 32C. (The computer case temperature is the important one, because the heatsink is trying to dump the heat into that ambient working temperature inside the case.) OK. Say I buy myself a heatsink with theta_R = 0.20C/W (degrees C per watt) Further, say the CPU is 67W. I run my 100% loading software, such as Prime95 or CPUBurn or an equivalent piece of software. Now I want to calculate the expected CPU temperature. Expected = case_ambient + ( theta_R * CPU_Power_watts ) = 32C + ( 0.20C/W * 67W ) = 45.4C Now, say I use a higher power processor, like an 89W one. = 32C + ( 0.20C/W * 89W ) = 49.8C It didn't make too much difference in that case, because the heatsink is a pretty good one. Some of the retail heatsinks that ship with processors, have been poorer, at about 0.33C/W as an example. *If* you had run the CPU at 100% loading on your 3200+, then it would be possible to measure the ambient case temperature (with something like Speedfan), and solve for theta_R. (You know both the case temp and the CPU temp, and the book value for the processor TDP watts.) Then, you could substitute the new power number (89W) and get an estimate of what to expect with a different processor. For a flexible version of Prime95, try this one. It will work with single or multiple core processors, and run one thread on each core. The first time you run it, it will ask if you want to "join GIMPS". Say no. Then, a custom dialog will pop up. Examine the total memory to be tested. On my 1GB computer, it will recommend a number like 767MB of memory to test. Change the number to something smaller than the recommended value, as then there will be a bit of memory left for your other software to be run. Say, try 200MB for example. The left-most menu has "stop" and "exit" options, to get rid of the program when you're done thermal testing. [URL]http://www.mersenne.org/gimps/p95v255a.zip[/URL] The above characterization exercise is only as good, as the real power dissipated, matches the "book" value of 67W. I've measured my processor, and it happens to come pretty close to the book value. But it doesn't have to. So working out your theta_R this way, will not be particularly accurate, but it should allow you to work out a ballpark figure for the impact of 30% more heat. But to do the measurement, you need a means to measure the case air temperature, the CPU temperature, and know the number of watts the CPU is using at the time. Then you can get the magic theta_R value in degrees C per watt. Paul [/QUOTE]

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