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Groth · 05-23-2003, 02:37 PM

That's better!

The whole 'don't boot until everything is cold' is easy to accomplish. Attach the thermistor to the cold plate, and use the output (high = cold enough) to drive a npn transistor spliced into the power_ok line, or a pnp transistor across the reset switch.

For a turn on temperature of 0C, the pot would be set to around 40k. The 150k resistor will give about 5 degrees of hysteresis; smaller = more hystereisis, larger = less.

A second copy will give overheat protection. Thermistor on the hot side, pot at 2-3k (60-70 C), output drives a pnp transistor across the ps_on line.

Soft shutdown - any ideas on how to get the temps into the computer?

05-23-2003, 02:37 PM	#27
Groth Cooling Savant Join Date: Mar 2003 Location: MO Posts: 781	That's better! The whole 'don't boot until everything is cold' is easy to accomplish. Attach the thermistor to the cold plate, and use the output (high = cold enough) to drive a npn transistor spliced into the power_ok line, or a pnp transistor across the reset switch. For a turn on temperature of 0C, the pot would be set to around 40k. The 150k resistor will give about 5 degrees of hysteresis; smaller = more hystereisis, larger = less. A second copy will give overheat protection. Thermistor on the hot side, pot at 2-3k (60-70 C), output drives a pnp transistor across the ps_on line. Soft shutdown - any ideas on how to get the temps into the computer?