Matrix Orbital Corp

Running LCDC 1.05.27 on a WinXP Pro, Athlon XP, VIA KT333 computer system. Have a MO LK202-24-USB configured to run as a digital baybus. Have a temp sensor from MO hooked up to the unit, along with some case fans.

All case fans are programmed to keep the temp sensor at about 35 deg C. Usually, this works fine. When temp below 35, the fans rev down to about 1200 RPMs. When the temp kicks up above 35, the fans rev up to 100%, or about 3500 RPMs.

However, I have a problem when the unit fails to rev up the fans even when the temp registers above 35 deg C. Once, it hit 39 deg without even revving up the fans.

This problem seems to occur when my computer's CPU is running at or near 100% for prolonged periods (ie. when I'm encoding video files). If I stop the display, then start it again, everything seems to reset and go back to normal.

However, I'm quite perplexed as to why the unit seems to choke when the CPU usage hits near 100%. I know it's registering the correct temp because the display shows the probe temp above 35 deg when this happens. It just seems the unit "Forgets" it's supposed to rev up the fans when this happens.

Any thoughts on the cause, or a possible fix? Hope I don't have a defective unit!

Thanks,
GCPien

One thing you can do is add a screen to show the GPOStatus (will show % value that the software sets the fan to) so we can work out if it's software or hardware.

Will do. I have added a GPOStatus screen, and will post a reply when I experience this problem again.

Thanks!

Well the temp probes registered at 35.4 deg C, but the fans were only spinning at 1500 RPM. The GPOStatus showed 29%.

I stopped the display, then restarted it. After doing so, the temp probes again registered 35.4 deg C, the fans revved to 3500 RPM, and the GPOStatus was 100%.

Odd, huh?

What have you set as the default start/stop value for the GPO? if it stayed down at 1500rpm at 34.5 that's right if your target temp is 35?

mat-d-rat

if you read my post carefully, you'll see that the current temp was 35.4 (not 34.5). therefore, my target temp of 35 should have had the fans revved up.

my target temp setting is 35. my min PWM is 20, my start/stop setting is 100%.