m2-atx failure? mobo doesn't post..

**bmbr** · 03-29-2006, 01:11 PM

So yesterday I was driving along when my VGA cable fell out slightly, causing the screen to distort. I leaned over and pushed it in, and when I did I heard a small pop across the speakers, and the epia motherboard powered off.

I pulled over and restarted it only to find that the motherboard wouldn't power on using my on/off switch attached to my m2-atx. I turned the ignition off, and back on which started the PC, only it did not post. The cpu fan goes full speed, no video is given, but the line-in (sirius) does play at a very loud volume

.

I went home and brought the epia mobo into a regular power supply on my bench and verified that it was able to post. I took it back out to my car, verified all of my connections, and looked for popped fuses (none). I then tried it again with the same results.

To summarize:

On/Off switch doesn't respond.
Turns on with ignition, but does not turn off (have to remove power from the m2-atx).
No POST, no video output.

Does it sound like that pop i heard was something on the m2-atx? That's the only thing I can think of in this scenario, but it confuses me that it still powers on. It confuses me even more that the PS is somehow causing the PC to not post.

In the interim I have it all unplugged for safety and I am driving around with no music. So sad

Any ideas on this one? Thanks guys!

**RawsonDR** · 03-29-2006, 03:43 PM

Got a multimeter? It would probably be helpful to probe the ATX connector when the PSU is powered up.
And the fact that the PC does not shut off when ignition goes low makes sense, because the M2 only sends a momentary pulse to tell Windows to shut down. With a switch, you'd have to hold it down to cut power.

With the fans spinning up, but no post, it's likely that the damage is localized to one or two components on the board - possibly something delivering 5V as that rail may be drawn upon for some of the VGA pins. I'm surprised the PSU failed with no damage to the motherboard, as it would have had to pass the current to the VGA cable.

**bmbr** · 03-29-2006, 04:12 PM

Originally Posted by RawsonDR

Got a multimeter? It would probably be helpful to probe the ATX connector when the PSU is powered up.

I have one in the truck, I will go check it in a bit and report back.

Originally Posted by RawsonDR

And the fact that the PC does not shut off when ignition goes low makes sense, because the M2 only sends a momentary pulse to tell Windows to shut down. With a switch, you'd have to hold it down to cut power.

I have an external switch connected to the m2-atx that allows manual control of the motherboard. I held it for 15+sec with no shutdown, nor does the mobo boot by trying to start with the button. I used the same switch, but connected directly to the mobo when I took it inside and it worked fine.

**bmbr** · 03-29-2006, 05:19 PM

I went at the ATX connector with the multimeter and found NO 5v lead. I found many that were less than .025 (fluctuating), and one that was slightly over 12v and one that was slightly over -12v.

Given that, it does sound like you might be onto something with regards to the 5v rail.

Any ideas? Also is this an issue that I should contact the manufacturer about? I bought this thru mp3car.com, but i'm not sure who actually makes it. minibox? anyone have an email address handy...

**bmbr** · 03-29-2006, 06:54 PM

Well, I went ahead and emailed support at mp3car.com, and they are RMA'ing my PSU for me! Best support response ever.

Just another reason why we should all continue buying from mp3car.com!

**Miles** · 03-30-2006, 06:12 PM

Originally Posted by bmbr

Well, I went ahead and emailed support at mp3car.com, and they are RMA'ing my PSU for me! Best support response ever.

Just another reason why we should all continue buying from mp3car.com!

That's awesome to hear!! I have similar issues with my new M2-ATX, but it seems to be some sort of compatibility issue w/ my Sp13000? That's not confirmed or anything, just seems to be common..

That said, iTuner is sending me a modified power supply free of charge!! Again, I love the support this community gets from the suppliers!

**bash1979** · 03-30-2006, 06:50 PM

Wow Miles, that's also good news!

If I remember correctly, I believe you were having the same "power on" issues I'm having with my M2-ATX/SP13000 combo. Did you originally purchase your M2-ATX from iTuner? Or did you buy elsewhere and contact iTuner directly when you experienced issues?

I'm just trying to figure out the best way for me to get a new PSU ("best" = least amount of downtime for CarPC...when it works, I'm hooked on this thing!!

)

**Miles** · 03-30-2006, 08:31 PM

Originally Posted by bash1979

Wow Miles, that's also good news!

If I remember correctly, I believe you were having the same "power on" issues I'm having with my M2-ATX/SP13000 combo. Did you originally purchase your M2-ATX from iTuner? Or did you buy elsewhere and contact iTuner directly when you experienced issues?

I'm just trying to figure out the best way for me to get a new PSU ("best" = least amount of downtime for CarPC...when it works, I'm hooked on this thing!!

)

Yeah, I hear ya about being hooked on it

I bought directly from iTuner, and Andrei was very easy to work w/ with and willing (without me even asking!!) to ship out a 'modified' M2-ATX.

Side note: doing some goofing around w/ it last night, if I let it post and then power it off, and then repeat this approx 5-6 times, it does eventually boot and operate normally.

Really hope the new M2-ATX version fixes this...

**DaveB** · 03-30-2006, 08:54 PM

The wire that goes from the M2-ATX J8 connector to the 2 pins on the motherboard header, which is for the power switch connection on the motherboard, is polarity sensitive. The M2-ATX will do some weird things if the connector on the MB is 180 degrees backwards. If the PC isn't powering off and on the way it should, try flipping that connector on the MB pins 180 degrees.

Also, the M2-ATX acts strange until you have had uninterrupted power to the J1 connector and booted the PC one time. After it has booted once, then things seem to act the way they should. If you remove power to J1, such as what happens when you shut off your power supply on your bench, then the M2-ATX will act strange again. Because of this, you will get different test results on the bench then you will get in the car. Unless you have some means of maintaining constant power to J1 when working on your bench and testing.....

It took me a while before I learned about the quirks of the M2-ATX. I almost tossed it in favor of a different PSU because it just acted so darn strange (inconsistent). What I didn't know was I created a lot of the problems for myself with not knowing about the two oddities I mentioned above.