Mac -Mini running at 100C CPU temperature after receiving back from servic

Question

Hello,
I just received back my Mac-mini from Apple service.
As other users reported, the fan was going mad, running at full speed all the time. By using: http://www.bresink.de/osx/TemperatureMonitor.html
I could see that the temperature-sensor connected to the heat-sink did not show up in the list of sensors. Service replaced the main board, and now the heat-sink sensor shows reasonable readings, and the fan is running silent, at least with no work load.
However, while performing a little web browsing, I found that the fan still goes wild.
What I noticed: The "TemperatureMonitor" utility reports that the CPU core temperature goes up beyond 100C/212F, even under mild work load, while the CPU heat sink is still reported at moderate temperatures around 35 C/95F !??? Environment temperature is below 30C.
Before I give away my MAC for another week or two, I would like to check whether this is usual behavior. Other users report max CPU temp of about 80-90C. Intel specifies max core temperature of 100C. According to the digital thermometer build in, my MAC sometimes exceeds this max spec by Intel.
Is this usual behavior, or did Apple service not properly install the heat sink after service, such that the CPU is only running with limited cooling ??
Thank you for your suggestions
Detlef
Mac Mini 1.5GHz core solo   Mac OS X (10.4.9)  

Answer 1

Only an internal investigation would show whether the heatsink was correctly reinstalled, but quite clearly since the temperature being reported is at the operational limit specified for the processor, what you are experiencing is not in any way 'usual'. There are sites with content such as flash animations, which can cause high CPU load and thus push system temperatures up and cause the fan to spin up, but not for prolonged periods of course.
Since the fan is running up to full speed on your mini as a result of the temperature rising, it is clearly not an issue with MacOS or the fan control cable, and as such I would urge that you return your system to the service provider with a description of the problem and a list of website addresses you have visited which causes these problems so they can set about replicating the issue.