Computer becomes unresponsive, inverter problem?

**tsb4k** · 03-25-2005, 07:24 PM

I'm running an old p2 system on a 200W inverter and it has started behaving oddly. The computer runs flawlessly when I run an extension cord into the trunk, or for the first few minutes when I run it off the inverter with the car running. Then usually a few minutes into driving the music stops and I am unable to reconnect to the computer.

The problem is that I use a PDA to stream music from the computer in the trunk, so it's hard to tell exactly what is going wrong. When the stream cuts off, I can't browse the network or remotely log into the computer. I know the computer isn't going to sleep or powering down the wireless, because it works just fine off of house power.

The part that kills me is that I ran nearly the exact same system (except for a new motherboard) in the glovebox and it worked fine. Change the motherboard and move the computer to the trunk and kaput. Argh! Was the old motherboard just more resistant to inverter hiccups?

**Curly_cat** · 03-26-2005, 02:27 AM

Can you swap back in the old mobo and try it? Sounds definitley like a power issue.

**tsb4k** · 03-26-2005, 01:44 PM

Unfortunately the old mobo is dead.

I'm frustrated because there are too many variables. The computer works off of house power so maybe its the inverter. Or what if its the combination of the inverter and power supply that killed my old mobo and is now doing the same to my new one?

**KyleYankan** · 03-26-2005, 02:21 PM

Originally Posted by tsb4k

Unfortunately the old mobo is dead.

I'm frustrated because there are too many variables. The computer works off of house power so maybe its the inverter. Or what if its the combination of the inverter and power supply that killed my old mobo and is now doing the same to my new one?

It runs fine from house power? Then it's the inverter, i'd say. Try looking into a new one. a 400w inverter costs $30 with s/h on ebay.

Try testing your current invter. Unplug everything from it, then plug something close to the 200w range into it, and see if it can handle it. Also, try running the car in the driveway, until your pc turns off or "stop streaming". Pop the trunk, and test the power with a multimeter.

**Scouse Monkey** · 03-26-2005, 03:41 PM

sounds like you could be losing the hard drive. Listen to your HDD to see if it is clicking on and off or spinning up and down erratically or when it seems to hang. this could be caused by a lack of power (eg when the CPU powers up or other things kick in) or a lose Molex connector (take it apart and close the connections) or a dodgy IDE cable. The cables could have been disturbed when you changed the mobo.

**tsb4k** · 03-26-2005, 08:37 PM

I took your advice and resecured the hd and all the cables, and it's still behaving strangely. The computer turns itself on when plugged into the inverter, which it never used to.

With the car idling it ran fine for a few minutes (after booting up spontaneously), so tomorrow I'll see if I can figure out what makes it fail when driving.

**Bugbyte** · 03-26-2005, 08:55 PM

If it worked fine with the car on, that's a bigger vote for a voltage problem. The car generates higher voltage when on than when off. The inverter may not be supplying enough voltage when the car is off. Measure the voltage out of the inverter and also the voltage out of the DC power supply with the car on and off.

**Scouse Monkey** · 03-28-2005, 04:39 PM

if your PC is booting when power is restored check the setting in the bios. Something could have caused a chane to your bios (it happens) so check other settings too. Or if the PSU is behaqving strange due to low voltages it could be that decinding to restart somehow. But more likely you bios resume from power fail setting or something.

**tsb4k** · 03-30-2005, 07:49 PM

Today I exchanged the inverter, just in case, and of course it didn't help.

I've checked the bios, and all the settings like "AC pwr loss restart" and "auto power up" are disabled.

I even replaced the power socket in the PSU with a filtered one, figuring it might be alternator noise creeping up into it, but that didn't help. The PSU buzzes slightly less now though.

Finally I tried to see if I could cause it to lock up, so I drove around at various rpms and it didn't freeze until I was sitting at a stop sign. When it happened I got out and checked the inverter and it was happily chugging away with no error codes or signs of distress.

Next up is to try a new PSU I guess.