upgraded my CPU fan ... first core is 64 degrees and 54 degrees Celsius in the second core, 51 third core and 56 fourth core in 2 minutes of stress. Is this temperature normal for the CPU?
Q9400 2.66GHz 95W
GAMMAXX 200T
SinaTPB,
As with other Intel Desktop processors, each individual Core has its own Digital Thermal Sensor (DTS) which function independently of the other. Intel's specification for DTS accuracy is +/- 5°C. This means that during an all-Core steady-state 100% workload such as Prime95 > Small FFTs which applies equal workloads to all Cores, the deviation between the highest and lowest Cores should not exceed 10°C. You can also use OCCT > CPU > Small > Normal > Steady which is nearly identical to Prime95 > Small FFTs. Both are extremely similar workloads within just a few percent power consumption of one another.
If you are NOT using an all-Core steady-state 100% workload as described above, and are instead using a fluctuating workload which might be primarily single threaded and not evenly loading all Cores, such as is typical with many games, then the deviation between Cores may exceed 10°C. As "stress" tests vary widely with respect to workload characteristics, patterns and power consumption levels, the key to properly conducting a valid thermal test is to use
only test software that fulfills the requirements for an all-Core steady-state 100% workload. This eliminates software variables so that results will be consistent, repeatable and easier to compare.
As my esteemed colleague,
Lutfij, pointed out, you posted a thread September 21st concerning Core temperatures for your Q9400. I answered your Thread and suggested that you read our Intel CPU Temperature Guide 2021, where information such as DTS accuracy, how to properly test thermal performance and the results you should expect are discussed in detail.
If you did use Prime95 Small FFTs (Blend is a fluctuating workload, so use ONLY Small FFTs) and your highest to lowest deviation in Core temperature is indeed 13°C (as the values you provided suggest), then an uneven application of "paste" (thermal compound) between the cooler and the "IHS" (Integrated Heat Spreader) is often the cause. However, unlike Core i 3rd through 8th Generation which have paste between the IHS and the silicon "Die", your earlier Core 2 Quad Q9400 instead has "solder" between the IHS and the Die, which has very rarely ever been found to be the cause of excessive temperature deviation between the highest and lowest Cores.
Please confirm
exactly which stress test(s) you ran.
CT
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