Motherboard beeps when weather gets colder...

**bash1979** · 11-01-2008, 12:18 PM

Hey guys,

I've been battling this problem every winter since I first installed my CarPC a few years back.

First, the key specs:
SP13000 mobo
M2-ATX PSU
40gb Hitachi Endurastar HD (rated to -30 degrees)
512mb Kingston RAM

Basically, as soon as the weather starts getting a bit chilly (usually around late October here), the CarPC will spin up, then emit a constant series of BEEEEP....BEEEEP....BEEEEP.....etc until the machine is powered off. This continuous beep every second or so allegedly indicates a memory issue, according to my searches. I've tried re-seating the memory and installing a new chip with no success. During this time, nothing is displayed on the monitor...just the annoying beeps fill the car.

Of course, as soon as the car gets warm, the PC will boot up just fine. Likewise, if I were to immediately remove the beeping CarPC from the car and bring it into the house and attach it to my test bench, it will also boot up fine.

I know it's not a hard drive problem, because the Endurastar is rated for very cold temperatures (plus, the mobo never posts or gets around to even detecting the HD).

I'm leaning towards and issue with the M2-ATX, but I don't understand how cold weather would affect it. And I'm not talking about freezing temperatures here....we're currently hovering at around 5 degrees Celcius (~41 Fahrenheit).

Any ideas/suggestions would be GREATLY appreciated!

Thanks,
Bash

**Punky** · 11-01-2008, 01:38 PM

Its definitely not the endurstar, i have it and its works fine well below -10C.
I'd double check on the spec of the mobo/psu. There was a thread on mobo temp, and i recalled seeing people posted the SP13000 mobo operational temp. Search around and u'll see.

**bash1979** · 11-02-2008, 03:53 PM

Originally Posted by Punky

Its definitely not the endurstar, i have it and its works fine well below -10C.
I'd double check on the spec of the mobo/psu. There was a thread on mobo temp, and i recalled seeing people posted the SP13000 mobo operational temp. Search around and u'll see.

Thanks for the reply.

By the book, the SP13000 says "Operating Temperature, - 0~50°C". I've personally got it working in temperatures below zero before, but since I'm still experiencing these problems at 5 or 10 degress Celcius, I'm thinking that rules out the mobo. Then again, maybe my mobo is just sensitive! :P

Anyone else out there having weather-related issues with the SP13000?

**bash1979** · 01-18-2009, 04:55 PM

Seems like the problem is getting worse...

Now I'm not even getting any beeps....only the fan spins up and that's about it.

I've always thought it's because of the cold, but here's the funny part: If I bring a standard desktop PSU out to the garage, and plug the carpc into it, it boots up perfectly fine right away! As soon as I switch back to the car battery powering the M2-ATX, I'm back to square one. At the very least, I think this proves my components will run in cold temperatures, but only if they receive the right amount of juice from a clean power source.

So, I took some readings with a multimeter and can see that when the car is turned on, I'm getting 11.9 volts to the M2-ATX. I know it's looking for 12, but you gotta figure that 11.9 is enough, no?

One small thing of note....not sure if it matters, but I do get a very quick reading of 11.6 when the car is turned on, then it jumps to 11.9. Could this quick variation be causing the problem by not giving the M2-ATX enough juice to boot?

Any ideas would be greatly appreciated!

**PaulF** · 01-18-2009, 05:22 PM

That power supply can actually accept anywhere from 6-24 volts input. It may however, not be getting enough current.

11.9 volts is actually low in a car. It should be up around 13-14 when the car is running. This might be indicating a faulty alternator or battery. Don't take my word as law though, someone with more knowledge than me may be able to give you a better response.

**skuller** · 01-21-2009, 01:34 PM

The voltage should be over 13v when the engine is running so the battery can be charged.
It can be the power cable to the battery causing voltage drop (very unlikely though)

**bash1979** · 01-24-2009, 06:12 PM

Thanks for the tips, guys.

Other than checking the voltage like I am, is there another way to check to see if a battery is bad? Maybe take it to a shop and have them do some kind of diagnostic?