(c) Scott M Baker,


What does it do?

This program is designed to monitor the LM78 Microprocessor System Hardware Monitor. The LM78 chip is installed in most recent (1997 or older) motherboards. It provides the following system monitoring functions: Temperature, Fan RPM, and Voltage. Output is displayed in a graphical format with a thermometer for temperature, angular gauge for RPM, LED's for voltage, etc. Real-time stripcharts are supported to display measurements that change over time.

How do I know if my motherboard has an LM78?

If your motherboard is old (pre-1997), then it probably doesn't. If it's new, then it probably does. I'd suggest just running the program and seeing what happens. You can always look on the motherboard itself for something labelled "LM78". You can look in your motherboard manual for information about system monitoring. If your motherboard came with software for monitoring fan RPM, temperature, and voltage, then it probably does.

I do know for a fact that the Supermicro P6DLS does support it. That's the motherboard I use.

What if my motherboard doesn't have an LM78?

Then it probably isn't going to work...

So who cares about these measurements?

I wrote the program mainly because a friend of mine was bothering me abot the LM78 and thought we could do some cool things with it. In theory, if you suspect that your machine has a problem with temperature, voltage, or fan RPM, then it might be useful to you.

The voltages look strange... Whats wrong?

The voltage readings for the LM78 may be determined by some resistor ratios; I'm really not sure. I had to calculate the multipliers for the SuperMicro MB by hand, and I think they are fairly correct for that motherboard. I have included a field where you can enter your own voltage multipliers on the Setup page.

If there is demand, and sufficient information, then I anticipate adding additional preload settings for other motherboard manufactures to the setup page.


I would like to thank national SSD for their LM78VXD driver, and the information data sheet on the LM78 chip.

Revision History

If you wish to contact me, you can find me at the following:



US Mail:

Scott M Baker
2241 W Labriego
Tucson, Az 85741