It depends on the Software. MBM-5, and CPUCool use different diodes, or Thermistors to monitor software, and most times you have to assign these diode/thermistor addresses. Especially with MBM-5 there's a specific diode it monitors which will set al the alarms off, because it's insanely high. I've seen it read either 157C or -84C and it's simply re-setting it to another on the list. It's usually the second diode fo the CPU. I'll bet my solder-dropping collection, it's just reading the wrong device. The CPU should be about 20C above the Motherboard diode reading, depending on cooling. In my case I use some extreme watercooling placement, and usually my CPU temps are 5C to 11C below my mobo temp.
This is employing the DD RBX with Nozzle-5 installed (it truly replicates the Cascade's impingment into cup design) the rubber gasket, and the multiple holes cut into the lucite on the number-5 directs mutiple streams into the RBX's heat-voids. I know many eschew the RBX design in favor of "real" H20 blocks. Lest we forget at one time Danger Den was the PolarFLO and Cascade innovator of it's time. They've done a lot bringging real water-cooling to the market, and dare I say Koolance as well. Please don't flame me for mentioning the latter.
The reason my temps are so low is location, location, and location, of components, and the case.
Anyway I'll get back to ya with specific thermistor assigment in MBM