Temp Diode

Processor Temp Diode Information

I went ahead and did a whole bunch of heatsink testing today utilizing the processor diode of the Celeron 300a for temperature data. I used MotherBoard Monitor to get the diode temperature and Prime95 to load the processor for 30 minutes. I ran the processor at 450MHz and 2.0 volts for the data below since that is what most folks will be able to compare with the easiest. I also tested some of the heatsinks at 504MHz and the temperature differences were much greater between each heatsink. The ALPHA P125 stayed about the same but the others climbed significantly.

Celeron 300a @ 450MHz (2.0 volts)

HEATSINK	CPU DIODE	RT2	RT1
ALPHA P125	43 C	28 C	29 C
Global VEK12	48 C	33 C	30 C
Global FAB28	51 C	35 C	31 C
TennMax Celeron TF	52 C	35 C	32 C
Global FAB24	52 C	36 C	32 C
Glacier 4500C	54 C	38 C	33 C
Global FAB04	55 C	37 C	34 C
COFAN KC-266	55 C	38 C	34 C
Cool Master CP2-5010	56 C	39 C	34 C
Intel Celeron Retail	56 C	40 C	35 C

All the testing was done utilizing my reference system and with an ambient air temperature of 25C. The RT2 header was connected to a thermistor which was placed between the heatsink and processor against the cpu slug as close as possible to the same location for each heatsink. The RT1 temperature is of course the "system" temperature as reported by the WinBond chip on the BX6-2 motherboard. It is interesting to note how the RT1 temperature increased slightly with the increasing temperatures of the less capable heatsinks. I thought the system temperature would have stayed relatively the same without regard to the other temperatures since the case ventilation was the same during all the testing. Please keep in mind if you compare your own diode temperatures to my data that my system has several case ventilation fans which may cause the temperatures to be lower then in most other systems.

There have been a lot of folks emailing me with difficulties getting MBM to work correctly with their BX6-2. Here are the settings I am using...

WinBond W83782D (should auto-detect during application installation)

There are three sensor readings available, they set set as follows for the BX6-2:

Sensor 1 : WinBond 2 - P2 thermal diode (processor temperature diode)

Sensor 2 : WinBond 3 (BX6-2 RT2 header temperature)

Sensor 3 : WinBond 1 (BX6-2 RT1 "system temperature")

I have used these settings with the BETA BIOS and now the newest KH BIOS and they work fine.

MBM will not work correctly for me if I have Hardware Doctor also running.

For those of you with the BX6-2 mobos that are missing the required parts to read the thermal diode I have an image showing the component location on the board from Benchtest.com.

Click on image for a higher detail view.

For some excellant detailed information on the BX6-2 and the componants that some are missing including where they can be obtained check out Benchtest.com .