CPU fan speed too high with S5500HCVR motherboard

[idata]

I recently built a dual-X5675 processor system with an S5500HCVR motherboard. The case is an Antec Titan 550 server enclosure that came without a power supply, so I used a SilverStone ST60F-P (600W).

It booted up fine, I installed Ubuntu 11.10 64-bit, and all was fine initially. Even when running heavy simulations it was relatively quiet. Then, since the firmware was out of date (S5500.86B01.00.0050) I updated to the lastest version and ran into trouble updating the FRUSDR. It noted that it couldn't find a temperature sensor and wasn't an Intel case. I chose the option "Other" for the chassis, indicated that both CPU 1 and CPU 2 had their CPU fans plugged into the CPU1 Fan and CPU2 Fan headers on the motherboard, and that the system fan wasn't connected to any of the SYSFAN headers.

On rebooting, the CPU fans went to maximum and were insanely loud. The only way I've found to quiet them somewhat is to redo the FRUSDR update and choose "no" for all options, i.e. say that neither of the CPU fans or the system fan are attached to the mobo fan headers. If I do this the CPU fans are quieter, but still considerably louder than before the updated the firmware. They appear to run a constant speed the whole time.

Does anyone have a suggestion about how I can fix this, or, better yet, how I can restore the firmware on the board to the factory default version it had when I bought it?

This system will run in a relatively cold lab, and will be used for simulations. I don't care about RAS, monitoring or any of the usual server considerations. All I want is lots of cores, with CPU fans that throttle according to the temperature of the processor.

[Edward_Z_Intel]

When "Other" chassis is selected, all fans run at full speed by default. To change this behavior, you'll need to manually edit the SDR file and do thermal test by your self.

For more information about modifying the SDR file, check the following post:

/message/93150# 93150 http://communities.intel.com/message/93150# 93150

[DSilv11]

Not sure that is the SDR edit I would recommend.

The values indicated will slow the fans, they will also prevent them from speeding up of needed.

Best choice is to add a front panel temp sensor, but you can edit the SDR as describe in this POST to use the baseboard temp sensor instead of the front panel sensor,

Check this POST /message/140265# 140265 http://communities.intel.com/message/140265# 140265

[idata]

Okay, thanks for the suggestions guys. I'll have a go at editing the SDR file.

Thanks again.

[idata]

For anyone reading this thread in the future:

Editting the HC_BMR.sdr file as per the links above did the trick. I told the firmware to use the baseboard thermal sensor (number 20) instead of the front panel thermal sensor (sensor number 21) in all sections. I also altered the minimum and maximum processor fan speeds as a function of temperature for the "Other" chassis selection. Finding the right speeds as a function of temperature is a bit of a black art, though.

Thanks again to those that made suggestions!